Entry Type ID Date Applicable Rating System Prerequisite/Credit Inquiry (LIs) Ruling (LIs) Related Addenda/LIs Related Resources Campus Applicable Internationally Applicable Country Applicability Reference Guide (Addenda) Page (Addenda) Location (Addenda) Description of Change (Addenda) "Form Update" "5000015" "2014-10-01" "New Construction, Core and Shell, Schools - New Construction, Retail - New Construction, Healthcare, Data centers - New Construction, Hospitality - New Construction, Warehouse and distribution centers - New Construction, Commercial Interiors, Retail - Commercial Interiors, Hospitality - Commercial Interiors, Existing Buildings, Schools - Existing Buildings, Retail - Existing Buildings, Data centers - Existing Buildings, Hospitality - Existing Buildings, Warehouse and distribution centers - Existing Buildings" "None" "Outdoor Water Use Reduction Calculator" "X" "Initial release of the Outdoor Water Use Reduction Calculator (international version of EPA's WaterSense calculator with SI units). Form changes include adding references to the new Outdoor Water Use Reduction Calculator and adding SI units to the additional reductions section." "Reference Guide Correction" "100001966" "2014-10-01" "New Construction, Core and Shell, Schools - New Construction, Retail - New Construction, Healthcare, Commercial Interiors, Retail - Commercial Interiors" "100000754, 10116" "None" "X" "Green Building Design and Construction, 2009 edition and Green Building Design and Construction, 2009 edition, updated June 2010 and Green Interior Design and Construction, 2009 edition and Green Interior Design and Construction, 2009 edition, updated June 2011 " "BD+C 174, ID+C 106" "Design Case Water Consumption" "Private or private use applies to plumbing fixtures in residences, apartments, and dormitories; private (non-public) bathrooms in transient lodging facilities (hotels and motels); and private bathrooms [and patient rooms] within hospitals and nursing facilities.\n\n Add the following to eligible fixtures section:\n\n ""For healthcare projects, fixtures used for clinical use related to medical procedures, such as surgical scrub sinks and exam rooms sinks, in hospitals and medical office buildings are excluded from the water use calculations. Medication room sinks, utility room sinks, and other exam/procedure/observation room sinks for clinical use are also excluded. Should exam/procedure/observation room sinks be used primarily for hand-washing, they may be included in the water use calculations at the project team’s discretion under the public lavatory category. If included, project teams should provide a narrative explaining the usage assumptions for these sinks.\n Lavatories in hospital inpatient bathrooms and inpatient rooms are considered private. The inpatient lavatory and water closet should use the default residential usage assumptions (of five times per day per residential occupant), unless specific project conditions warrant an alternative. Lavatories in hospital inpatient rooms (outside the bathrooms) are considered private if used by patients and/or staff similarly to a residential lavatory, or can be exempt if they are used by staff primarily for medical or clinical use.\n\n Nutrition station (pantry) sinks and hospital staff lounge sinks should be included in the water use calculations under the kitchen sink category."" " "Reference Guide Correction" "100001914" "2014-10-01" "New Construction, Core and Shell, Schools - New Construction, Retail - New Construction, Healthcare, Data centers - New Construction, Hospitality - New Construction, Warehouse and distribution centers - New Construction, Commercial Interiors, Retail - Commercial Interiors, Hospitality - Commercial Interiors, Existing Buildings, Schools - Existing Buildings, Retail - Existing Buildings, Data centers - Existing Buildings, Hospitality - Existing Buildings, Warehouse and distribution centers - Existing Buildings" "None" "International Water Labeling Programs" "X" "BD+C 279; ID+C:99; O+M: 145, 170" "Further Explanation, International Tips" "Replace ""Projects in unlisted countries must comply with the 20%-below-baseline requirement but have no additional performance requirements"" with: ""Project outside the U.S. must meet WaterSense flush and flow rates.""\nn Change to Guidance document:\n ""Projects in countries listed in the WaterSense Equivalencies section of the International Water Labeling Programs document must select fixtures with the designated label in place of the WaterSense requirement.\n\n Countries without a listed labeling program must meet the following flush and flow requirements: (Table 6 minus private lav and kitchen sinks) \n\n *Tank type toilets only. Flushometer toilets do not have an equivalent requirement for WaterSense."" " "Reference Guide Correction" "100001912" "2014-10-01" "New Construction, Core and Shell, Schools - New Construction, Retail - New Construction, Healthcare, Data centers - New Construction, Hospitality - New Construction, Warehouse and distribution centers - New Construction" "None" "None" "X" "301" "Further Explanation, Project Type Variations" "Add Additions to Project Type Variations – \n\n Additions\n For credit compliance, include in the credit documentation all plumbing fixtures necessary to meet the occupants’ needs whether they will be installed as part of the project’s scope of work or not. Include at a minimum all necessary restroom fixtures (toilets, urinals, and lavatories) to meet the project occupants’ needs, and showers when seeking LT Credit Bicycle Facilities. The WaterSense label requirement does not apply to fixtures that are outside of the scope of the LEED project. " "Regional ACP" "100001973" "2014-10-01" "New Construction, Core and Shell, Schools - New Construction, Retail - New Construction, Healthcare, Commercial Interiors, Retail - Commercial Interiors" "None" "None" "Europe" "Green Building Design and Construction, 2009 edition" "BD+C RG 2nd ed: 165" "Requirements" "Projects in Europe may use values defined by European Standards. " "Regional ACP" "100001970" "2014-10-01" "New Construction, Core and Shell, Schools - New Construction, Retail - New Construction, Healthcare, Commercial Interiors, Retail - Commercial Interiors" "None" "None" "Europe" "Green Building Design and Construction, 2009 edition" "BD+C RG 2nd ed: 165" "Requirements" "Projects in Europe may use values defined by European Standards. " "Form Update" "5000016" "2014-10-01" "New Construction, Core and Shell, Schools - New Construction, Retail - New Construction, Healthcare, Data centers - New Construction, Hospitality - New Construction, Warehouse and distribution centers - New Construction, Commercial Interiors, Retail - Commercial Interiors, Hospitality - Commercial Interiors, Existing Buildings, Schools - Existing Buildings, Retail - Existing Buildings, Data centers - Existing Buildings, Hospitality - Existing Buildings, Warehouse and distribution centers - Existing Buildings, Neighborhood Development plan, Neighborhood Development" "None" "Indoor Water Use Calculator" "X" "Fixed errors in previous version including uses per day calculation. Added override functions for special circumstances, modified built-in dual flush calculator, added custom naming of tabs and streamlined output fields Added Neighborhood Development calculations" "Form Update" "5000025" "2014-10-01" "New Construction, Core and Shell, Schools - New Construction, Retail - New Construction, Healthcare, Data centers - New Construction, Hospitality - New Construction, Warehouse and distribution centers - New Construction, Commercial Interiors, Retail - Commercial Interiors, Hospitality - Commercial Interiors" "None" "None" "X" "X" "For CS projects only, added tenant lease agreement upload and narrative describing future tenant plumbing fixtures to WE Credit Indoor Water Use Reduction section. Throughout form, added instructional notes clarifying when field values should be based on developer-installed fixtures versus future tenant plumbing fixtures. " "Reference Guide Correction" "100001831" "2014-07-01" "New Construction, Core and Shell, Schools - New Construction, Retail - New Construction, Healthcare, Data centers - New Construction, Hospitality - New Construction, Warehouse and distribution centers - New Construction, Commercial Interiors, Retail - Commercial Interiors, Hospitality - Commercial Interiors" "None" "None" "X" "BD+C: 300; ID+C: 106" "Step-By-Step Guidance, Step 2" "Remove ""seawater"" from list of untreated water sources ineligible for this credit.\n Add ""treated seawater"" to the list of acceptable alternative water sources, behind stormwater. " "Form Update" "5000008" "2014-07-01" "New Construction, Core and Shell, Schools - New Construction, Retail - New Construction, Healthcare, Commercial Interiors, Retail - Commercial Interiors, Existing Buildings" "None" "2009 Water Use Reduction Calculator" "X" "X" "Corrected errors from previous version, including incorrect uses per day calculation. Added override functions for special circumstances. Modified built-in dual flush calculator. Added functionality for custom naming of tabs. Streamlined output fields. Added content for BD+C, ID+C, and Retail/Healthcare project types." "LEED Interpretation" "10284" "2013-10-01" "New Construction" "In what Water Efficiency credits may desalinated seawater be applied as a non-potable water source?" "Desalinated seawater that is not treated to potable drinking water standards may be applied as a non-potable water source in the following credits:\n - WEc1 Water Efficient Landscaping\n - WEc2 Innovative Wastewater Technologies\n - WEc4 Cooling Tower Water Management (in LEED-EBOM)\n - WEc4.2 Water Use Reduction – Cooling Towers (in LEED-Healthcare)\n - WEc4 Process Water Use Reduction (in LEED-Schools for other (non-food service) equipment types such as cooling towers)\n\n Refer to the guidance document Applicability of Seawater in Water Efficiency credits.\n\n Desalinated seawater may NOT be applied in WEp1/c3 Water Use Reduction. The focus of the water use reduction prerequisite and credit is fixture efficiency and on-site water reuse. Because sourcing water from the sea does not constitute a form of water reuse, desalinated seawater is not applicable to WEp1 regardless of whether the seawater is treated on-site or off-site.\n\n In order to take credit for using desalinated seawater as a non-potable water source in applicable Water Efficiency credits, the desalinated seawater must be:\n 1) Municipally supplied or explicitly approved by the municipality for on-site treatment systems,\n 2) Meet all applicable code and permitting requirements so as to not contaminate the system served with high salinity,\n 3) Treated to an appropriate level for non-potable uses, and\n 4) The on-site energy use to desalinate the seawater must be included in the EAp2/EAc1 calculations.\n\n Note that seawater is water from a sea or ocean. Salty groundwater or brackish well water in coastal areas is not considered non-potable seawater. Groundwater and water sourced from naturally occurring surface water bodies, such as streams, rivers, and lakes is also not applicable. Only seawater sourced directly from a sea or ocean may be applied.\n" "1551, 10211, 10212, 2163, 10117" "Seawater guidance" "X" "Rating System Correction" "100001787" "2013-04-01" "New Construction, Existing Buildings, Commercial Interiors, Core and Shell, Schools - New Construction" "100000920, 100000753, 100000990, 100001788" "None" "X" "Green Building Design and Construction, 2009 edition $ Green Building Design and Construction, 2009 edition, updated June 2010 $ Green Interior Design and Construction, 2009 edition $ Green Interior Design and Construction, 2009 edition, updated June 2011 $ Green Building Operations and Maintenance, 2009 edition $ Green Building Operations and Maintenance, 2009 edition, April 2010 updated" "BD+C RG 1st ed: 171 $ BD+C RG 2nd ed: 171 $ BO+M RG 1st ed: 87 $ BO+M RG 2nd ed: 87 $ ID+C RG 1st ed: 105 $ ID+C RG 2nd ed: 105" "Table 2a for BDC and IDC and Table 3a EBOM" "Autocontrol faucet baseline Addenda (all rating systems). In the 2/2/2011 Addenda, replace the baseline in the related note below table with “Default duration for the metering type / autocontrol lavatory faucet is 0.25 gallons per cycle (gpc) for the baseline case and 12 seconds for the design case.” " "LEED Interpretation" "10276" "2013-04-01" "New Construction, Core and Shell, Schools - New Construction, Retail - New Construction" "For campus projects, can wastewater treatment facilities located outside of the LEED project boundary but within the campus boundary qualify as on-site for the purposes of this credit? " """Yes, campus projects may utilize a wastewater treatment facility located outside of the LEED project boundary as long as it is within the campus boundary for Option 2. Treated water must be infiltrated or used on-site by the project. Please note that a campus scale wastewater treatment facility located outside of the LEED project boundary would be considered a municipally supplied non-potable water source for all other Water Efficiency credits, and would not be considered an on-site non-potable water source in WEp1 Water Use Reduction. Applicable Internationally."" " "None" "None" "X" "X" "Reference Guide Correction" "100001696" "2012-10-01" "New Construction, Core and Shell, Schools - New Construction" "None" "None" "Green Building Design and Construction, 2009 edition $ Green Building Design and Construction, 2009 Edition, updated June 2010 " "BD+C RG: 177" "Definitions, blackwater" "Replace the first sentence with, ""Blackwater is wastewater containing urine or fecal matter that should be discharged to the sanitary drainage system of the building or premises in accordance with the International Plumbing Code.""" "Reference Guide Correction" "100001697" "2012-10-01" "New Construction, Core and Shell, Schools - New Construction" "None" "None" "Green Building Design and Construction, 2009 edition $ Green Building Design and Construction, 2009 Edition, updated June 2010 " "BD+C RG: 190" "Definitions, graywater" "Replace the definition of ""graywater"" with ""Graywater is untreated household waste water which has not come into contact with toilet waste. Graywater typically includes used water from bathtubs, showers, bathroom wash basins, and water from clothes-washer and laundry tubs, though definitions may vary. Some states and local authorities also allow kitchen sink wastewater to be included in graywater. Project teams should comply with the graywater definition established by the authority having jurisdiction in the project area.""" "Reference Guide Correction" "100001698" "2012-10-01" "New Construction, Core and Shell, Schools - New Construction" "None" "None" "Green Building Design and Construction, 2009 edition $ Green Building Design and Construction, 2009 Edition, updated June 2010 " "BD+C RG: 201" "Definitions, blackwater" "Replace the first sentence with, ""Blackwater is wastewater containing urine or fecal matter that should be discharged to the sanitary drainage system of the building or premises in accordance with the International Plumbing Code.""" "Global ACP" "100001219" "2012-07-06" "New Construction, Core and Shell, Schools - New Construction" "None" "None" "X" "Green Building Design and Construction, 2009 edition $ Green Building Design and Construction, 2009 Edition, updated June 2010" "NC, CS RS: 30, Schools RS: 36" "Commercial Fixtures , Fittings, and Appliances table" "For showerhead metric units, change ""5 bar (58 psi)"" to ""5.5 bar (80 psi)""" "Global ACP" "100001220" "2012-07-06" "New Construction, Core and Shell, Schools - New Construction" "None" "None" "X" "Green Building Design and Construction, 2009 edition $ Green Building Design and Construction, 2009 Edition, updated June 2010" "NC, CS RS: 30, Schools RS: 36" "Commercial Fixtures , Fittings, and Appliances table" "In the pre-rinse spray valve row, add ""(6 lpm)"" after ""1.6 gpm""" "Global ACP" "100001221" "2012-07-06" "New Construction, Core and Shell, Schools - New Construction" "None" "None" "X" "Green Building Design and Construction, 2009 edition $ Green Building Design and Construction, 2009 Edition, updated June 2010" "NC, CS RS: 30, Schools RS: 36" "Residential Fixtures , Fittings, and Appliances table: Current Baseline (Metric Units)" "Revise the Current Baseline (Metric units) for Residential showerheads cell to read ""9.5 lpm at 5.5 bar (80 psi) per shower stall""" "Global ACP" "100001211" "2012-07-06" "New Construction, Core and Shell, Schools - New Construction" "None" "None" "X" "Green Building Design and Construction, 2009 edition $ Green Building Design and Construction, 2009 Edition, updated June 2010" "NC RS: 25, CS RS: 25, Schools RS: 31" "Commercial Fixtures , Fittings, and Appliances table" "For showerhead metric units, change ""5 bar (58 psi)"" to ""5.5 bar (80 psi)""" "Global ACP" "100001212" "2012-07-06" "New Construction, Core and Shell, Schools - New Construction" "None" "None" "X" "Green Building Design and Construction, 2009 edition $ Green Building Design and Construction, 2009 Edition, updated June 2010" "NC RS: 25, CS RS: 25, Schools RS: 31" "Commercial Fixtures , Fittings, and Appliances table" "In the pre-rinse spray valve row, add ""(6 lpm)"" after ""1.6 gpm""" "Global ACP" "100001213" "2012-07-06" "New Construction, Core and Shell, Schools - New Construction" "None" "None" "X" "Green Building Design and Construction, 2009 edition $ Green Building Design and Construction, 2009 Edition, updated June 2010" "NC RS: 25, CS RS: 25, Schools RS: 31" "Residential Fixtures , Fittings, and Appliances table: Current Baseline (Metric Units)" "Delete ""Except blow out fixtures: 13 lpf"" from the Current Baseline (Metric units) for Residential toilets cell." "Global ACP" "100001214" "2012-07-06" "New Construction, Core and Shell, Schools - New Construction" "None" "None" "X" "Green Building Design and Construction, 2009 edition $ Green Building Design and Construction, 2009 Edition, updated June 2010" "NC RS: 25, CS RS: 25, Schools RS: 31" "Residential Fixtures , Fittings, and Appliances table: Current Baseline (Metric Units)" "Delete ""4 lpm"" and "", private applications only (hotel or motel guest rooms, hospital patient rooms) 2.0 lpm at 4 bar (58 psi), all others except private applications 1 liter per cycle for metering faucets"" from the Current Baseline (Metric units) for Residential lavatory (bathroom faucets) and Residential kitchen faucet cell." "Global ACP" "100001215" "2012-07-06" "New Construction, Core and Shell, Schools - New Construction" "None" "None" "X" "Green Building Design and Construction, 2009 edition $ Green Building Design and Construction, 2009 Edition, updated June 2010" "NC RS: 25, CS RS: 25, Schools RS: 31" "Residential Fixtures , Fittings, and Appliances table: Current Baseline (Metric Units)" "Revise the Current Baseline (Metric units) for Residential showerheads cell to read ""9.5 lpm at 5.5 bar (80 psi) per shower stall""" "Global ACP" "100001216" "2012-07-06" "New Construction, Core and Shell, Schools - New Construction" "None" "None" "X" "Green Building Design and Construction, 2009 edition $ Green Building Design and Construction, 2009 Edition, updated June 2010" "NC RS: 25, CS RS: 25, Schools RS: 31" "Residential Fixtures , Fittings, and Appliances table" "In the **** note, add ""/9.5 lpm)"" after ""(2.5 gpm""" "Global ACP" "100001217" "2012-07-06" "New Construction, Core and Shell, Schools - New Construction" "None" "None" "X" "Green Building Design and Construction, 2009 edition $ Green Building Design and Construction, 2009 Edition, updated June 2010" "NC, CS RS: 27, Schools RS: 33" "Option 1. Reduce by 50%" "Add ""or using the month with the highest irrigation demand."" to the end of the first sentence." "Global ACP" "100001218" "2012-07-06" "New Construction, Core and Shell, Schools - New Construction" "None" "None" "X" "Green Building Design and Construction, 2009 edition $ Green Building Design and Construction, 2009 Edition, updated June 2010" "NC, CS RS: 28, Schools RS: 34" "Requirements" "Delete the Alternative Compliance Path for Projects Outside the U.S. box." "Global ACP" "100001222" "2012-07-06" "New Construction, Core and Shell, Schools - New Construction" "None" "None" "X" "Green Building Design and Construction, 2009 edition $ Green Building Design and Construction, 2009 Edition, updated June 2010" "NC, CS RS: 30, Schools RS: 36" "Residential Fixtures , Fittings, and Appliances table" "In the **** note, add ""/9.5 lpm)"" after ""(2.5 gpm""" "LEED Interpretation" "10210" "2012-07-01" "New Construction, Core and Shell, Schools - New Construction, Retail - Commercial Interiors" "Can an alternative compliance path for WEc1.2 Water Efficient Landscaping, No Potable Water Use or No Irrigation be created by demonstrating that an equal or greater amount of rainwater, required for irrigation, is reused on site, while irrigating a portion of the landscape with potable water?" "This strategy, while positive, does not adequately address the intent of the credit to limit or eliminate the use of potable water resources for landscape irrigation. As long as there is a 50% reduction in potable water, one point will be earned regardless of the irrigation source and one additional point is earned when no potable water is used for irrigation and there is a 50% reduction in Total Water Applied (TWA). While the project is correct in suggesting that the avoided energy and lower operating costs justifies the design approach, this is not a deciding factor in this credit. Internationally applicable." "None" "None" "LEED Interpretation" "10211" "2012-07-01" "New Construction, Existing Buildings, Commercial Interiors, Core and Shell, Schools - New Construction, Retail - New Construction, Retail - Commercial Interiors, Healthcare" "Can municipally supplied treated seawater for toilet flushing be used as a strategy for earning WEp1 and WEc1 Water Use Reduction?" "No, municipally supplied sources of non-potable water, including seawater, are not applicable to the WE fixture water use reduction credits, including WEp1 (D+C, EBOM) and WEc1 (CI) Water Use Reduction, or considered graywater. As stated in LI 1551 (12/12/2006) This credit focuses on fixture efficiency and on-site water reuse. In addition, the Water Use Reduction Additional Guidance document (updated 8/16/2010, http://www.usgbc.org/ShowFile.aspx?DocumentID=6493), confirms that the focus of the prerequisite is water efficiency of the installed fixtures, regardless of the water source, and only on-site water reuse is available as an alternative compliance path. \n However, municipally treated wastewater (including treated seawater) applies to SSc1 - Path 9 Innovative Wastewater Technologies (CI), WEc2, Innovative Wastewater Technologies (BD+C), and can be used if the two conditions of LEED Interpretation 10117 are met: 1) the seawater is municipally supplied or explicitly approved by the municipality and 2) meets all applicable codes and permitting requirements, so as not to contaminate the municipal wastewater system with high salinity. For EBOM projects, where no wastewater credit is available, the project may apply for innovation credit for use of this strategy.\n\n **Update October 1, 2013: Note that LEED Interpretation 10117 has been updated to clarify that seawater must be treated to appropriate levels for non-potable uses in order to apply to WEc2 Innovative Wastewater Technologies; seawater that is treated to potable drinking water standards would not apply. Any on-site energy use to desalinate the seawater must be included in the EAp2/c1 calculations. Refer to the guidance document. Applicability of Seawater in Water Efficiency credits also updated." "1551, 10117, 10212, li-10284, 10284" "Seawater guidance" "LEED Interpretation" "10212" "2012-07-01" "New Construction, Existing Buildings, Commercial Interiors, Core and Shell, Schools - New Construction, Retail - New Construction, Retail - Commercial Interiors, Healthcare" "Can municipally supplied treated seawater for toilet flushing be used as a strategy for earning WEp1 and WEc1 Water Use Reduction?" "No, municipally supplied sources of non-potable water, including seawater, are not applicable to the WE fixture water use reduction credits, including WEp1 (D+C, EBOM) and WEc1 (CI) Water Use Reduction, or considered graywater. As stated in LI 1551 (12/12/2006) This credit focuses on fixture efficiency and on-site water reuse. In addition, the Water Use Reduction Additional Guidance document (updated 8/16/2010, http://www.usgbc.org/ShowFile.aspx?DocumentID=6493), confirms that the focus of the prerequisite is water efficiency of the installed fixtures, regardless of the water source, and only on-site water reuse is available as an alternative compliance path.\n\n However, municipally treated wastewater (including treated seawater) applies to SSc1 - Path 9 Innovative Wastewater Technologies (CI), WEc2, Innovative Wastewater Technologies (BD+C), and can be used if the two conditions of LEED Interpretation 10117 are met: 1) the seawater is municipally supplied or explicitly approved by the municipality and 2) meets all applicable codes and permitting requirements, so as not to contaminate the municipal wastewater system with high salinity. For EBOM projects, where no wastewater credit is available, the project may apply for innovation credit for use of this strategy.\n\n **Update October 1, 2013: Note that LEED Interpretation 10117 has been updated to clarify that seawater must be treated to appropriate levels for non-potable uses in order to apply to WEc2 Innovative Wastewater Technologies; seawater that is treated to potable drinking water standards would not apply. Any on-site energy use to desalinate the seawater must be included in the EAp2/c1 calculations. Refer to the guidance document. Applicability of Seawater in Water Efficiency credits also updated." "1551, 10117, 10211, li-10284, 10284" "Seawater guidance" "LEED Interpretation" "10213" "2012-07-01" "New Construction" "Our project is an Army standard Company Operations Facility (COF) which consists of office and warehouse modules. The Army standard design for this building type requires both the office and warehouse modules, and while these components are typically combined under one roof, the standard allows for a detached configuration based on site conditions and user preference. For this project, the detached configuration will be used with a conditioned warehouse module detached from (but adjacent to) the office module. In accordance with the Army Standard for COF facilities, the warehouse module is not permitted to have restroom facilities since they are provided in the office module and the Army mandates the consolidation of plumbing fixtures in one location. The absence of dedicated toilets or fixtures in the warehouse module may prevent it from meeting the Water Efficiency prerequisite 1 under LEED NC if registered as a standalone building. Can the separate office and warehouse modules for this project be registered as one building?" "UPDATE 10/1/2012 - This Ruling has been retracted because it is project-specific. It is no longer applicable as of 10/01/2012. It can only be used by Army standard Company Operations Facilities projects registered or submitted for review between 7/1/12 and 8/30/12. Similar project types will be evaluated on a case by case basis.\n\nThe project team is inquiring if the Army standard Company Operations Facility (COF) which consists of office and warehouse modules can be considered a single building even for instances where the components may be detached. Yes, the Company Operations Facility can be considered a single building. The fact that the components of the COF are tied together and only a single set of plumbing fixtures is provided between the components indicates that they operate as a single building even when detached. " "None" "None" "LEED Interpretation" "10214" "2012-07-01" "New Construction, Existing Buildings, Core and Shell, Schools - New Construction" "Can a LEED-NC project without eligible water fixtures be exempt from WEp1 Water Use Reduction?" "A project without eligible water fixtures in the LEED-NC project boundary is exempt from WEp1. Should such a project wish to pursue points under WE Credit 3, they may do so by evaluating WEc3 performance based upon all of the fixtures that are necessary to meet the needs of the project occupants, even if they are located outside the project boundary.\n **Update October 1, 2012: Has been made applicable to LEED for Schools v2007 and v2009.\n **Update October 1, 2013: Applicable credits were updated. This ruling does not apply to Core and Shell projects." "None" "None" "LEED Interpretation" "10215" "2012-07-01" "New Construction" "Should prison fixtures be included or excluded from WEp1 and WEc3 (WEc1 in CI) Water Use Reduction calculations?" "Beginning with projects registered after 7/1/2012, prison water closets (toilets), urinals and safety showerheads must be included in water use reduction calculations for fixtures and fittings. This LI overturns the older LI 5033 (applicable to projects registered before 11/1/2011) and expands on the language of LI 10120 (applicable to projects registered between 11/1/2011 and 7/1/2012). Fixture use assumptions for prisoners follow the default fixture assumptions for residential occupants. Accordingly, lavatory faucets, toilets, and showerheads serving prisoners must follow the residential fixture requirements, baselines, and daily usage assumptions for the purposes of this prerequisite/credit. Internationally applicable. Internationally applicable.\n\n***Update 1/1/13: This LI is applicable to LEED NC v2.2" "5033, 10120, 10216" "None" "LEED Interpretation" "10216" "2012-07-01" "New Construction" "Should prison fixtures be included or excluded from WEp1 and WEc3 (WEc1 in CI) Water Use Reduction calculations?" "Beginning with projects registered after 7/1/2012, prison water closets (toilets), urinals and safety showerheads must be included in water use reduction calculations for fixtures and fittings. This LI overturns the older LI 5033 (applicable to projects registered before 11/1/2011) and expands on the language of LI 10120 (applicable to projects registered between 11/1/2011 and 7/1/2012). Fixture use assumptions for prisoners follow the default fixture assumptions for residential occupants. Accordingly, lavatory faucets, toilets, and showerheads serving prisoners must follow the residential fixture requirements, baselines, and daily usage assumptions for the purposes of this prerequisite/credit. Internationally applicable.\n\n***Update 1/1/13: This LI is applicable to LEED NC v2.2" "5033, 10120, 10215" "None" "LEED Interpretation" "10217" "2012-07-01" "New Construction, Existing Buildings, Core and Shell, Schools - New Construction, Retail - Commercial Interiors, Neighborhood Development" "Should athletic fields be included or excluded from landscape water use calculations for WEc1?" "All LEED projects can choose to include or exclude athletic fields at the project teams discretion from WEc1 Water Efficient Landscaping (D+C) and WEc3 Water Efficient Landscaping (EBOM). However, if such areas are included, they must be included in all other applicable credit calculations. Internationally applicable." "None" "None" "Reference Guide Correction" "100001169" "2012-04-01" "New Construction, Schools - New Construction, Core and Shell, Healthcare, Retail - New Construction" "100001178, 100001170" "None" "Green Building Design and Construction, 2009 edition $ Green Building Design and Construction, 2009 Edition, updated June 2010 " "BD+C RG: 177" "Definitions" "In alphabetical order, add the following definition for autocontrol faucets, ""Autocontrol faucets have automatic fixture sensors or metering controls.""" "LEED Interpretation" "10155" "2012-04-01" "New Construction, Existing Buildings, Core and Shell, Schools - New Construction, Retail - Commercial Interiors, Healthcare, Neighborhood Development" "The intent of this credit is to alter planting details to eliminate the use of potable water for landscape irrigation as much as possible. Project teams tend to interpret ""landscape"" as any vegetated space on the project site. However, some projects also include growing space for food in an urban agriculture or community garden setting. This is not ""landscape"" in the usual sense, and the normal water use reduction measures aren\'t appropriate when the land is being used productively. In LEED for Homes, an existing LEED Interpretation clarifies that growing space should be exempted entirely from the calculations for the Homes version of this credit (do not include in the numerator or denominator). See LI 2736. I request that this LI be extended to all LEED rating systems, since growing space is potentially a component of many project types." "Project teams may elect to exclude food gardens from landscape calculations on the rationale that normal water use reduction measures are not appropriate when the land is being used to produce food for human consumption. If a project team chooses to exclude a food garden from the landscape area, it should be excluded uniformly across the baseline and design calculations. " "2736" "None" "Reference Guide Correction" "100001069" "2011-11-01" "New Construction, Core and Shell" "100001065, 100001066, 100001067, 100001070, 100001071" "None" "Green Building Design and Construction, 2009 edition$Green Building Design and Construction, 2009 Edition, updated June 2010 " "BD+C RG: 170" "NC & CS box, Calculating Occupancy" "At the end of the section, insert the following text as a new paragraph:\n\n""For hospitality projects, FTE and transient occupants are calculated per the typical methodology for the respective occupancy types. Hotel guests may be determined based on the number and size of units in the project. Generally, assume 1.5 occupants per guest room and multiply the resulting total by 60% (average hotel occupancy per AH&LA information) to determine the total number of hotel guests. Alternatively, occupants may be derived from actual historical occupancy numbers. \n\nFixture use assumptions for hotel guests follow the fixture assumptions for residential occupants. Accordingly, lavatories located in guest rooms are considered to be private lavatories. Additionally, day use guests at the hotel should be included in the value for transient / visitor occupants. Per typical fixture use assumptions, this category of occupants assumes zero shower uses throughout the day. \n\nExample: 123-room hotel\nTotal Hotel Guests = 123*1.5 * 60%\nTotal Hotel Guests = 111""\n" "Reference Guide Correction" "100001070" "2011-11-01" "New Construction, Core and Shell, Schools - New Construction" "100001065, 100001066, 100001067, 100001069, 100001071" "None" "Green Building Design and Construction, 2009 edition$Green Building Design and Construction, 2009 Edition, updated June 2010 " "BD+C RG: 170" "Fixture Usage Groups" "At the end of the section, insert the following text as a new paragraph:\n\n""For hospitality projects, fixture usage groups generally include a usage group for guest rooms and a usage group for common areas and back of house. For the purposes of the credit calculations, assume that hotel guests use the fixtures and fittings in their room, employees use back of house and / or common areas, and transient guests use common area restrooms. """ "Reference Guide Correction" "100001071" "2011-11-01" "New Construction, Core and Shell, Schools - New Construction" "100001065, 100001066, 100001067, 100001069, 100001070, 100001770, 100001771" "None" "Green Building Design and Construction, 2009 edition $ Green Building Design and Construction, 2009 Edition, updated June 2010 " "BD+C RG: 174" "Eligible Fixtures" "Below the first paragraph, enter the following text as a new paragraph:\n\n""For hospitality projects, commercial kitchen sinks and bar sinks including pot sinks, prep sinks, wash down, and cleaning sinks are considered process water and are not included in the water use calculations. Hand washing sinks located in commercial kitchen areas that do not pass through a grease interceptor should be included in the water use calculations under the kitchen sink category.""\n" "Rating System Correction" "100001068" "2011-11-01" "New Construction, Core and Shell, Schools - New Construction" "None" "Water use reduction BDC addenda 11/01/2011" "Green Building Design and Construction, 2009 edition" "NC RS: 25, CS RS: 25, Schools RS: 31" "Requirements" "Replace first table of the section " "Reference Guide Correction" "100001072" "2011-11-01" "New Construction, Core and Shell, Schools - New Construction, Retail - New Construction, Healthcare" "None" "Water use reduction BDC baseline table addenda 11/01/2011" "Green Building Design and Construction, 2009 edition $ Green Building Design and Construction, 2009 Edition, updated June 2010 $ Retail Supplement to Green Building Design and Construction, 2009 edition $ Healthcare Supplement to Green Building Design and Construction, 2009 edition" "BD+C RG: 165" "NC, SCHOOLS & CS box" "Replace first table of the section " "Reference Guide Correction" "100001073" "2011-11-01" "New Construction, Core and Shell, Schools - New Construction, Retail - New Construction, Healthcare" "None" "Water use reduction WEc3 BDC RG addenda 11/01/2011" "Green Building Design and Construction, 2009 edition $ Green Building Design and Construction, 2009 Edition, updated June 2010 $ Retail Supplement to Green Building Design and Construction, 2009 edition $ Healthcare Supplement to Green Building Design and Construction, 2009 edition" "BD+C RG: 203" "NC, SCHOOLS & CS box" "Replace first table of the section " "Rating System Correction" "100001074" "2011-11-01" "New Construction, Core and Shell, Schools - New Construction, Retail - New Construction, Healthcare" "None" "Water use reduction WEc3 BDC RS addenda 11/01/2011" "Green Building Design and Construction, 2009 edition" "NC RS: 30, CS RS: 30 , Schools RS: 36" "NC, SCHOOLS & CS box" "Replace first table of the section " "LEED Interpretation" "10115" "2011-11-01" "New Construction, Core and Shell, Retail - New Construction, Commercial Interiors, Retail - Commercial Interiors, Existing Buildings, Retail - Existing Buildings" "This is an inquiry about the calculation of the FTE in relation to our project in Zurich, Switzerland. \n\nIn the LEED Reference Guide on page 53 the calculation of the FTE is based on a 8-hour working day. That means that an 8-hour occupant has an FTE value of 1.0. The standard working day in Switzerland contains 8.5 hours of work.\n\nIn a FTE calculation on the basis that is provided in the LEED Reference Guide the normal working day of one single person would have the FTE value of 1.0625. As a consequence of the, in case of 1000 people fulltime staff this FTE calculation would have additional number of 63 FTE in comparion to an FTE value of 1.0.\n\nIs it possible to calculate the FTE value for this project with an 8.5 instead of 8 hour day, so that we would have the FTE value of 1.0 for a standard 8.5 hour-working day?" "The project team has inquired if projects in Switzerland may use 8.5-hours as their working day instead of 8-hours as in the US. Each full-time employee based on Swiss and US labor laws works an 8.5-hour day, which includes a half-hour unpaid lunch break and two 15-minute paid breaks. In order to maintain the baseline for projects everywhere when calculating FTE occupancy, all Swiss projects, including those industries that have an overtime work culture for full-time employees, should still use the 8.0-hour work day in their FTE calculations. Applicable internationally." "None" "None" "X" "LEED Interpretation" "10116" "2011-11-01" "New Construction, Existing Buildings, Commercial Interiors, Core and Shell, Retail - New Construction, Retail - Commercial Interiors, Neighborhood Development" "Does a single-occupant lockable bathroom in a commercial establishment count as ""private"" for flush & flow rate calculations?" "The project team is requesting a ruling on whether restrooms at a commercial establishment that are only usable by one individual or family at a time are considered private or private-use facilities. The facilities that are usable by one individual or family at a time at a commercial establishment are not considered private or private-use facilities. The private or public categories for lavatory faucets are based on the UPC and IPC Standards for plumbing fixtures, and are referring to the anticipated uses and performance expectations of such faucets. Public restroom faucets are used almost exclusively for hand washing or simple rinsing, compared to lavatory faucets in homes and in other private bathrooms that are used for various purposes. Therefore the single occupancy restroom facilities at a commercial establishment are not private-use facilities and the baseline case must be calculated according to the public lavatory faucet baseline flow rate. Applicable internationally." "100001966" "None" "X" "LEED Interpretation" "10117" "2011-11-01" "New Construction, Core and Shell, Schools - New Construction, Retail - Commercial Interiors" "Can a project use municipally supplied treated seawater for toilet flushing and earn credit under innovative wastewater?" "Treated seawater is acceptable for use for toilet flushing under the following conditions: 1) the water is municipally supplied or explicitly approved by the municipality and 2) meets all applicable codes and permitting requirements, so as not to contaminate the municipal wastewater system with high salinity. This source is considered innovative wastewater because it offsets the use of potable water from a fresh water source.\n\n **Update October 1, 2013: Note that seawater must be treated to appropriate levels for non-potable uses; seawater that is treated to potable drinking water standards would not apply. Any on-site energy use to desalinate the seawater must be included in the EAp2/c1 calculations. Refer to the guidance document. Applicability of WE credits also modified." "10211, 10212, li-10284, 10284" "Seawater guidance" "X" "LEED Interpretation" "10118" "2011-11-01" "New Construction, Schools - New Construction, Commercial Interiors, Core and Shell, Existing Buildings, Retail - New Construction, Retail - Commercial Interiors" "Can reverse osmosis reject water be used as an innovative wastewater source? Reverse osmosis water is often used in lab, hospital and other process water settings." "Yes, on-site reverse osmosis reject water is an acceptable non-potable water source. Applicable internationally." "None" "None" "X" "LEED Interpretation" "10119" "2011-11-01" "New Construction" "We are currently designing a new County Justice Center. The project consists of 193,338 gsf and will house the county jail, Courts and office space for the County Attorney, Community Corrections, Sheriff and Court Administration. The facility comprises an occupant load of 1,879 - 587 of which are attributable to the jail portion of the facility including the inmate population, staff and visitors. During the design development process, the project team has determined that the project will be able to achieve over 40% water efficiency for the project in the courts and office space of the project. However, due to the product availability, maintenance requirements and the behavioral nature of the inmate population we have determined that the project will be unable to use low flow fixtures for the jail portion of the building. Use of low flow fixtures will place an unreasonable burden on the construction project and negatively impact the ongoing operations and maintenance of the project. Not being able to use these fixture types will negate the water efficiency achieved in other portions of the building. We respectfully request that the jail portion of the facility be exempt from the water efficiency calculations and that these strategies be applied only to the Courts and Offices areas of the project." "In the definitions section of EPAct 1992 (Section 123, B) ""water closet"" and ""urinal"" fixtures installed in prisons are excluded. Also, the definition of ""showerhead"" excludes safety showerheads. Thus, these fixtures do not fall in the scope of this credit, and do not need to be included in the calculations for WEc3." "None" "None" "LEED Interpretation" "10120" "2011-11-01" "New Construction" "Can the jail portion of a prison facility be excluded from the water efficient toilet requirements of this credit due to the lack of product availability, maintenance requirements and the behavioral nature of the inmate population?" "There are now a sufficient number of stainless steel jail type toilets on the market at the 1.28 gpf level or below to make compliance with this prerequisite reasonable. Therefore, the jail portion of a prison facility is not exempt from the credit baseline and design calculations for LEED 2009 projects. Applicable Internationally.\n\n***This LI overturns LI 5033, for projects registered after 11/1/2011, and projects registered after 7/1/2012 must refer to LI 10216, which provides additional clarifications on this issue.\n\n***Update 1/1/13: This LI is applicable to LEED NC v2.2" "5033, 10216, 10215" "None" "X" "Reference Guide Correction" "100000987" "2011-08-01" "New Construction, Core and Shell, Schools - New Construction, Retail - New Construction, Healthcare" "None" "Water use reduction addenda 08/01/2011" "Green Building Design and Construction, 2009 edition $ Green Building Design and Construction, 2009 Edition, updated June 2010 " "BD+C RG: 175" "Figure 1" "See revised image" "Rating System Correction" "100000915" "2011-05-09" "New Construction, Core and Shell, Retail - New Construction" "None" "None" "Green Building Design and Construction, 2009 edition" "BD+C RG: 179, NC RS: 23, CS RS: 25,
Retail-NC RG supp: 45, Retail-NC RS: 19" "Footnote 1" "Replace the footnote text with the following:\n\nIf the percent reduction of potable water is 100% AND the percent reduction of total water is equal to or greater than 50%, then Option 2 is earned, for a total of 4 points." "Reference Guide Correction" "100000916" "2011-05-09" "New Construction, Schools - New Construction, Core and Shell, Retail - New Construction, Healthcare, Commercial Interiors, Retail - Commercial Interiors, Existing Buildings" "730, 808, 1166, 2465, 5044, 5291, 1866" "None" "Green Building Design and Construction, 2009 edition $ Green Interior Design and Construction, 2009 edition $ Green Building Operations and Maintenance, 2009 edition" "BD+C RG: 168, BO+M RG: 84, ID+C RG: 102" "4. Implementation" "Remove the paragraph beginning with, ""Although water-efficient dishwashers..."" " "Reference Guide Correction" "100000917" "2011-05-09" "New Construction, Schools - New Construction, Core and Shell, Retail - New Construction, Healthcare" "None" "None" "Green Building Design and Construction, 2009 edition" "BD+C RG: 211" "13. Definitions" "In alphabetical order, insert the term ""once-through (single-pass) cooling a system"" with the text ""A once-through (single pass) cooling system is one which water from any source is used to transfer heat from equipment or processes and then discharged." "Reference Guide Correction" "100000918" "2011-05-09" "New Construction, Schools - New Construction, Core and Shell, Retail - New Construction, Healthcare" "None" "None" "Green Building Design and Construction, 2009 edition" "BD+C RG: 172" "Schools box" "(1) In the ""Calculating Occupancy"" section, add ""e. Part-time students"" \n(2) In the paragraph immediately below that, before the last sentence, add ""Part-time students are calculated in the same manner as part-time staff.""" "Reference Guide Correction" "100000919" "2011-05-09" "New Construction, Schools - New Construction, Core and Shell, Retail - New Construction, Healthcare" "None" "None" "Green Building Design and Construction, 2009 edition" "BD+C RG: 169" "6. Calculations" "After the section\'s first paragraph, insert the following:\n\nFor additions to existing buildings, only the fixtures within the project scope must be counted for the prerequisite. To earn points under WE credit 3, all fixtures necessary to meet the needs of the addition occupants must be included, even if they are located within the existing building." "LEED Interpretation" "10010" "2011-05-09" "New Construction, Existing Buildings, Commercial Interiors, Core and Shell, Schools - New Construction" "The installation of bedside patient care units, which is a combined toilet and lavatory, is required for some patient rooms. Can the patient care unit be excluded from the calculations since there are no low-flow options available?" "All fixtures that are covered by the EPAct 1992 must be included in the credit calculations, even if there are no low-flow options available. The use of these fixtures by only the patients in a limited area can be factored into the calculations. " "None" "None" "LEED Interpretation" "10011" "2011-05-09" "New Construction, Existing Buildings, Core and Shell, Schools - New Construction" "Are calculations based on annual irrigation water use acceptable to earn the credit if it is demonstrated that annual water savings of 50% or greater, due to the use of a weather tracking controller and periods of no irrigation, can be achieved?" "Although the strategies used to decrease annual water savings are commendable, the proposed approach is not acceptable. In this credit, all calculations are based on July as a proxy for the peak water demand month. Applicable internationally." "100000756" "None" "X" "LEED Interpretation" "10012" "2011-05-09" "New Construction, Core and Shell, Schools - New Construction" "Can project team include reclaimed water systems that are planned and funded, but will not be completed until 3 to 5 years after occupancy in credit calculations?" "Per the LEED NC v2.1 WEc2 CIR ruling dated 10/2/2006, projects may only count future infrastructure such as reclaimed water systems so long as they will be completed and functional within 1 year. Applicable internationally." "None" "None" "X" "LEED Interpretation" "10013" "2011-05-09" "New Construction, Existing Buildings, Commercial Interiors, Core and Shell, Schools - New Construction" "Can untreated groundwater, unsuitable for drinking, contribute towards WE credits 1, 2, and 3 as a non-potable water source for irrigation and sewage conveyance?" " This approach does not meet the intent of the WE credits. Although the local groundwater may not be suitable for drinking straight out of the ground, it still represents an important source of potable water. Applicable internationally." "None" "None" "X" "LEED Interpretation" "10014" "2011-05-09" "New Construction, Existing Buildings, Commercial Interiors, Core and Shell, Schools - New Construction" "Are swimming pools excluded from the calculations for WE Prerequisite 1?" "This is correct as the prerequisite only covers fixtures specified in the Reference Guide and regulated by one of the standards listed. These fixtures and fixture fittings include water closets, urinals, lavatory faucets, showers, kitchen sink facets, and pre-rinse spray valves. Applicable internationally." "None" "None" "X" "LEED Interpretation" "10015" "2011-05-09" "New Construction, Existing Buildings, Commercial Interiors, Core and Shell, Schools - New Construction" "Can children\'s toilets be exempt from the prerequisite because there are no low-flow options available?" "There are children\'s toilets available that are 1.6 gpf. The project team must decide what is best for the clientele, but baby toilets cannot be exempt from the credit. Applicable internationally." "None" "None" "X" "Reference Guide Correction" "100000753" "2011-02-02" "New Construction, Schools - New Construction, Core and Shell" "100001787" "None" "Green Building Design and Construction, 2009 edition" "171" "Table 2a (see above)" "In the sixth row (""Lavatory Faucet"") row of the table in the 11/2/2009 addenda, replace the duration (sec) of 15 with 30; replace the related note below table with ""Default duration for the metering type / autocontrol faucet is 15 seconds for the baseline and 12 seconds for the design case.""" "Reference Guide Correction" "100000754" "2011-02-02" "New Construction, Schools - New Construction, Core and Shell" "5033, 100001790, 100001791, 100001966" "None" "Green Building Design and Construction, 2009 edition" "174" "Eligible Fixtures" "Replace the section text with the following:\n\nThis prerequisite is limited to savings generated by the following water using fixtures and fixture fittings as applicable to the project: water closets, urinals, lavatory faucets, showers, kitchen sink faucets and pre-rinse spray valves, as shown in Table 1. \n\nThe ""Kitchen sinks"" category encompasses all sinks in public or private buildings that are used with patterns and purposes similar to a sink in a residential kitchen; break room sinks would be included. However professional grade / commercial faucets such as those used in a commercial kitchen would not be included. The ""Public lavatory faucets"" and ""Private lavatory faucets"" categories encompass all sinks used primarily for hand-washing regardless of location. Faucets whose usage patterns and flow rates are regulated for medical or industrial purposes (e.g. laboratory sinks) and do not fall under the definition of private or public use are not included. Faucets used exclusively for filling operations (e.g. pot-filler) can be excluded. All other fixtures and fixtures fittings must be included in the calculations unless there are special circumstances that justify excluding them.\n" "Reference Guide Correction" "100000755" "2011-02-02" "New Construction, Schools - New Construction, Core and Shell" "1578" "None" "Green Building Design and Construction, 2009 edition" "183" "Technologies" "In the paragraph beginning with ""Using groundwater..."", replace the last sentence with the following:\n\nAdditionally the credit can be met when landscape irrigation is provided by raw water (excluding naturally occurring surface bodies of water, streams, or rivers, and ground water) that would otherwise be treated specifically for nonpotable uses. Only ponds designed solely for the purposes of stormwater retention or detention can be used for this credit.\n" "Reference Guide Correction" "100000756" "2011-02-02" "New Construction, Schools - New Construction, Core and Shell" "10011" "None" "Green Building Design and Construction, 2009 edition" "186" "Table 2" "Below the table, replace the first sentence of the paragraph with the following:\n\nDetermine, if applicable, the controller efficiency (CE), the percentage reduction in water use from any weather-based controllers or moisture sensor-based systems, not to exceed 30% for the peak month of July.\n" "Reference Guide Correction" "100000757" "2011-02-02" "New Construction, Schools - New Construction, Core and Shell" "None" "None" "Green Building Design and Construction, 2009 edition" "186" "Equation 3" "Replace ""CE"" with ""(1 - CE)""" "Reference Guide Correction" "100000330" "2010-07-19" "New Construction, Schools - New Construction, Core and Shell" "None" "None" "Green Building Design and Construction, 2009 edition" "169" "Table 1" "In footnote ""b,"" replace ""2.0 gmp"" with ""2.0 gpm""" "Reference Guide Correction" "100000333" "2010-07-19" "New Construction, Schools - New Construction, Core and Shell" "None" "None" "Green Building Design and Construction, 2009 edition" "173" "Design Case Water Consumption" "In the second line of the paragraph, remove the text ""and subtracting any nonpotable water supply""" "Reference Guide Correction" "100000334" "2010-07-19" "New Construction, Schools - New Construction, Core and Shell" "None" "None" "Green Building Design and Construction, 2009 edition" "174" "Table 4" "In the fifth row of the table in the column ""Flow rate,"" replace ""1.8 gpm"" with """"? 2.2 gpm""" "Reference Guide Correction" "100000335" "2010-07-19" "New Construction, Schools - New Construction, Core and Shell" "None" "None" "Green Building Design and Construction, 2009 edition" "174" "Table 4" "In the seventh row of the table in the ""Flow Fixture"" column, replace ""Low-flow shower"" with ""WaterSense shower""" "Reference Guide Correction" "100000336" "2010-07-19" "New Construction, Schools - New Construction, Core and Shell" "None" "None" "Green Building Design and Construction, 2009 edition" "174" "Table 4" "In the seventh row of the table in the ""Flow Rate"" column, replace ""1.8 gpm"" with ""? 2.0 gpm""" "Reference Guide Correction" "100000352" "2010-07-19" "New Construction, Schools - New Construction, Core and Shell" "None" "None" "Green Building Design and Construction, 2009 edition" "191" "13. Definitions" "Insert the term ""Landscape area"" in alphabetical order with the accompanying text ""The landscape area of the site is the total site area less the building footprint, paved surfaces, water bodies, areas being left in a natural state, and patios.""" "Reference Guide Correction" "100000337" "2010-07-19" "New Construction, Schools - New Construction, Core and Shell" "None" "None" "Green Building Design and Construction, 2009 edition" "174" "Paragraph below Table 4" "Replace the first sentence with ""Private or private use applies to plumbing fixtures in residences, apartments, and dormitories, to private (non-public) bathrooms in transient lodging facilities (hotels and motels), and to private bathrooms in hospitals and nursing facilities.""" "Reference Guide Correction" "100000338" "2010-07-19" "New Construction, Schools - New Construction, Core and Shell" "None" "None" "Green Building Design and Construction, 2009 edition" "176" "12. Resources" "In alphabetical order, insert the following text:\n\nAlliance for Water Efficiency\nhttp://www.allianceforwaterefficiency.org/\nThe Alliance for Water Efficiency provides information and\nassistance on water conservation efforts." "Reference Guide Correction" "100000339" "2010-07-19" "New Construction, Schools - New Construction, Core and Shell" "None" "None" "Green Building Design and Construction, 2009 edition" "176" "12. Resources" "Remove the following text:\n\nFine Homebuilding Choosing a Toilet\nhttp://www.taunton.com/finehomebuilding/pages/h00042.asp\nThis article includes several varieties of water-efficient toilets." "Reference Guide Correction" "100000340" "2010-07-19" "New Construction, Schools - New Construction, Core and Shell" "None" "None" "Green Building Design and Construction, 2009 edition" "176" "12. Resources" "In the resource ""Rocky Mountain Institute, Water,"" replace the text below the resource header with the following:\n\nhttp://www.rmi.org/rmi/pid172\nThis portion of RMI\'s website is devoted to water resource\nefficiency." "Reference Guide Correction" "100000341" "2010-07-19" "New Construction, Schools - New Construction, Core and Shell" "None" "None" "Green Building Design and Construction, 2009 edition" "176" "12. Resources" "Remove the following text:\n\nU.S. EPA, Water Use Efficiency Program\nhttp://www.epa.gov/owm/water-efficiency\nThis website provides an overview of EPA\'s Water Use Efficiency\nProgram and information about using water more efficiently." "Reference Guide Correction" "100000342" "2010-07-19" "New Construction, Schools - New Construction, Core and Shell" "None" "None" "Green Building Design and Construction, 2009 edition" "177" "12. Resources" "Replace the resource ""Water Closet Performance Testing,"" with the following:\n\nWater Studies\nhttp://www.ebmud.com/resource-center/publications/studies\nThe site provides a variety of studies related to water." "Rating System Correction, Reference Guide Correction" "100000343" "2010-07-19" "New Construction, Core and Shell, Schools - New Construction" "2207, 2552, 100000345, 100000346" "None" "Green Building Design and Construction, 2009 edition" " NC Rating System: 23, Schools Rating System: 27, CS Rating System: 25, Reference Guide: 179" "PATH 2" "Replace the second sentence of the paragraph with ""Temporary irrigation systems used for plant establishment are allowed only if removed within a period not to exceed 18 months of installation.""" "Reference Guide Correction" "100000345" "2010-07-19" "New Construction, Core and Shell, Schools - New Construction" "2207, 2552, 100000343, 100000346" "None" "Green Building Design and Construction, 2009 edition" "183" "Second paragraph on page (begins with ""Hose bibs"")" "In the second line, replace ""year"" with ""18 months"" so the text becomes ""...during the first 18 months of building...""" "Reference Guide Correction" "100000346" "2010-07-19" "New Construction, Core and Shell, Schools - New Construction" "2207, 2552, 100000343, 100000345" "None" "Green Building Design and Construction, 2009 edition" "183" "Second paragraph on page (begins with ""Hose bibs"")" "In the fifth line of the paragraph, replace ""1 year"" with ""18 months"" so the text becomes ""...a period of 18 months depending on...""" "Reference Guide Correction" "100000347" "2010-07-19" "New Construction, Schools - New Construction, Core and Shell" "None" "None" "Green Building Design and Construction, 2009 edition" "184" "SCHOOLS box" "Replace the second sentence with ""However, if such areas are included, they must be included in all other applicable Water Efficiency credit calculations (unless otherwise noted).""" "Reference Guide Correction" "100000349" "2010-07-19" "New Construction, Schools - New Construction, Core and Shell" "None" "None" "Green Building Design and Construction, 2009 edition" "185" "STEP 1" "At the end of the first paragraph, add the text ""Any area that is being improved upon (for example site area that is being restored to its natural state) must be included in the landscape area.""" "Reference Guide Correction" "100000350" "2010-07-19" "New Construction, Schools - New Construction, Core and Shell" "None" "None" "Green Building Design and Construction, 2009 edition" "188" "EXAMPLE 1" "In the first line of the first paragraph, replace the first sentence with ""An office building in Austin, Texas, has 6,000 square feet of landscape area.""" "Reference Guide Correction" "100000351" "2010-07-19" "New Construction, Schools - New Construction, Core and Shell" "None" "None" "Green Building Design and Construction, 2009 edition" "188" "EXAMPLE 1" "In the first line of the second paragraph, replace the first sentence with ""The baseline case uses the same reference ETo and total landscape area.""" "Reference Guide Correction" "100000354" "2010-07-19" "New Construction, Schools - New Construction, Core and Shell" "None" "None" "Green Building Design and Construction, 2009 edition" "208" "4. Implementation" "In the beginning of the first line of the first paragraph, insert the text ""With the exception of prerinse spray valves"" " "Reference Guide Correction" "100000325" "2010-07-19" "New Construction, Schools - New Construction, Core and Shell" "None" "None" "Green Building Design and Construction, 2009 edition" "167" "Environmental Issues" "Remove both instances of ""potable"" in the section" "Reference Guide Correction" "100000329" "2010-07-19" "New Construction, Schools - New Construction, Core and Shell" "None" "None" "Green Building Design and Construction, 2009 edition" "169" "Table 1" "In the fourth row of the table in the ""EPA WaterSense Standards"" column, replace ""1.5 - 2.0^b"" with ""2.0^b""" "Reference Guide Correction" "100000326" "2010-07-19" "New Construction, Core and Shell, Schools - New Construction" "None" "Water use reduction RG addenda 07/19/2010" "Green Building Design and Construction, 2009 edition" "168" "4. Implementation" "Replace the first three paragraphs with new text as indicated in the supplemental document." "Reference Guide Correction" "100000327" "2010-07-19" "New Construction, Schools - New Construction, Core and Shell" "None" "None" "Green Building Design and Construction, 2009 edition" "168" "4. Implementation" "In the first line of the fifth paragraph, replace the word ""conservation"" with ""efficiency"" so the text becomes ""...analyze the water efficiency options available...""" "Reference Guide Correction" "100000344" "2010-02-01" "New Construction, Schools - New Construction, Core and Shell" "None" "None" "Green Building Design and Construction, 2009 edition" "183" "Technologies" "In the second line of the last paragraph, remove the first instance of ""credit"" so the text becomes ""...an innovative way to achieve this credit.""" "Reference Guide Correction" "100000348" "2009-12-02" "New Construction, Schools - New Construction, Core and Shell" "None" "None" "Green Building Design and Construction, 2009 edition" "185" "STEP 1" "At the end of the second paragraph, remove the second period" "Reference Guide Correction" "100000331" "2009-11-02" "New Construction, Core and Shell, Schools - New Construction" "None" "Water use reduction addenda 11/02/2009" "Green Building Design and Construction, 2009 edition" "171" "Table 2" "Replace the table with two tables as indicated in the supplemental document. (Note: this table was updated again on February 2, 2011.)" "Reference Guide Correction" "100000332" "2009-11-02" "New Construction, Schools - New Construction, Core and Shell" "None" "None" "Green Building Design and Construction, 2009 edition" "173" "EXAMPLE 1" "In the fifth line of the paragraph, change the number 193 to 195, and the number 259 to 239, so it becomes ""...annual occupancy of 195 females and 239 males...""" "Reference Guide Correction" "100000328" "2009-11-02" "New Construction, Schools - New Construction, Core and Shell" "None" "None" "Green Building Design and Construction, 2009 edition" "169" "Table 1" "In the eighth row of the table in the ""Fixture"" column, remove the text ""and janitor"" so it becomes ""Kitchen sink faucets""" "LEED Interpretation" "5233" "2009-07-02" "New Construction, Existing Buildings, Core and Shell, Schools - New Construction" "Our project is seeking a ruling for LEED CS 2.0 WE credit 1.1-1.2, in regards to the specific circumstances for this project to recycle stormwater from a large manmade lake for landscape irrigation purposes and earn both WEc1.1 and 1.2. Background Our site is located on a former rock quarry. The quarry has been partially filled and flooded leaving a deep 12 acre manmade lake which is being recharged by runoff from a large adjacent urban zone. The project has incorporated native and adaptive species to reduce the landscape irrigation calculated total applied water use by over 50% and intends to utilize water from the non-potable source lake water for supplemental irrigation purposes to achieve both WEc1.1 and 1.2 through a 100% reduction in potable water use. A previous CIR ruling dated 9/5/2008 referred to a project that must document the stormwater coming in and going out of a pond to determine if the pond can meet the needs of the building and to compare projected pond levels to historical data. We have calculated that across the entire lake (530,996 sq. ft.), there would be a 0.274 inch/month drop due to irrigation use. The lake is being backfilled by a quarter acre to accommodate this project which will create a smaller basin and higher flows into it. Due to the dense urban surrounding of the project, we believe the runoff will easily accommodate this irrigation use. Calculating the inflows and outflows for the lake is not possible due to the unknown extent of the urban zone that is recharging the lake and historical data on the lake is not available. We intend to submit the LEED application within a short timeframe from the buildings opening and due to time constraints will not be able to verify performance of the irrigation system through measurements before the project submits. We intend to submit this credit in LEED online with the requirements as stated in the LEED CS reference guide and we would like a ruling as to whether our strategy will be sufficient to earn both WEc1.1 and WEc1.2 and if not, is there an alternative compliance path the project can take that does not involve a performance measurement time period." "The project is asking if a manmade lake, recharged with runoff, can be used for irrigation as a non potable water source, and count towards WEc1.2. It is unclear if the lake serves other uses, and if groundwater recharges the lake. If there is any groundwater present in the lake, then all three conditions of the 9/5/2008 CIR must be met. If the team can demonstrate that the lake is exclusively fed by stormwater, then stormwater and irrigation calculations must be provided for this and any future projects that may draw from the lake, indicating that over the course of the year, the water used for the project will not exceed the stormwater collected in the lake; and that in every month of the year the projected level of the pond shall not drop below historical average pond levels. Applicable Internationally. " "None" "None" "X" "LEED Interpretation" "2552" "2009-04-22" "New Construction" "Our landscape design on a major university campus utilizes exclusively native and adapted plantings. The university does not use permanent irrigation systems for the bulk of its campus landscapes. Accordingly, the project will incorporate a temporary system designed to support the needs of plantings during the initial establishment period. Aware that the USGBC allows temporary irrigation systems to operate for one year only, the maintenance staff have expressed serious concerns that this will not allow enough time for adequate plant establishment. It has been their experience that the soil, weather and seasonal extremes in this location require a minimum 2-year establishment period. The facility manager has used 1 year temporary systems in the past which led to the death of large plant material quantities and the loss of substantial economic resources. Upon reviewing previous CIRs, the design team noticed another project description which mentioned the use of temporary irrigation systems for a 2 year duration (see CIR for WEc1.2 dated 08.29.2005). In light of the direct experience of the maintenance staff, the language used in the ruling of the CIR mentioned above, and in the interests of conserving material and economic resources, the design team would like to attempt to satisfy WEc1.2 with a two year, temporary system. The design team would like to install the most cost-effective, environmentally sound and resource conservative irrigation system possible for the duration of the proposed 2 year plant establishment period. As such, we see significant economic and environmental disadvantages to using drip irrigation exclusively. Drip irrigation systems apply water to plant material more efficiently than spray heads and impacts but require more investment in labor and plastic tubing that will ultimately end up in a landfill. The proposed system will be a combination of impact heads and drip tubing where they are appropriate for the landscape type, surrounding site programming and character of the landscape aesthetic. While this practice will conserve more water than a traditional system because its short term use, it is unlikely to achieve 50% water use reduction compared to a baseline case. To clarify, are the temporary irrigation system allowed by credit WE1.2 subject to the 50% reduction in irrigation water use specified in WEc1.1? In addition, while it may be implied, we can find no place in the reference manual where it explicitly states that a temporary system can be run using potable water. Is this allowed?" "The project team is asking 3 questions concerning their temporary irrigation to be used for plant establishment. The first question is concerning the length of the plant establishment period. The LEED-NC 2.2 rating system states that temporary irrigation is allowed for plant establishment only if removed within one year. The CIR referenced is for a previous version of LEED-NC and is therefore not applicable to a LEED-NC 2.2 project. The second question is asking if the temporary irrigation system is required to meet the 50% water use reduction required by WEc1.1. There is no efficiency requirement for the temporary irrigation system, however a more efficient system that reduces the water consumption during the establishment period is of course encouraged. However, the project team should note the irrigation system installed must be temporary and easily removed. All or substantial portions of the irrigation system must be removed so as to disable the irrigation system after the one year establishment period. However, the strategies proposed are laudable and encouraged. The third question asked by the project is whether or not potable water is acceptable for temporary irrigation during the performance period. Potable water is allowable for the temporary irrigation within the plant establishment period. Any irrigation beyond the first year of establishment must be non-potable to meet the credit requirements of WEc1.2. Applicable Internationally. " "2207, 100000343, 100000345, 100000346" "None" "X" "LEED Interpretation" "2545" "2009-04-08" "New Construction, Existing Buildings, Core and Shell, Schools - New Construction" "The mechanical systems for this project are geothermal in design. Non-domestic use well water is supplied via a closed loop to an isolated heat pump heat exchanger to provide climate control of the building. The uncontaminated well water is then returned to the ground via a separate well, at a location different from where it was extracted. We would like to use a portion of this discharge well water for site irrigation. Our question is; will this water be considered a non-potable source to help achieve WE Credit 1.2? Our opinion is that this returned well water should be considered non-potable since its use in the irrigation system is secondary to the use of the geothermal system. Also, in using this water in the irrigation system, it is being applied to the landscape and provides a positive impact on the ground water table in the fact that it will replace soil moisture that would have been evaporated from the soil surface and therefore diminishing the moisture levels deeper within the soil profile. A certain portion of this water will also migrate through the soil profile back into the water table." "The applicant is requesting approval to use water extracted from the outlet of an open-loop ground source heat pump for irrigation. The proposed approach does not satisfy the intent of the credit. The irrigation water would be provided indirectly from natural subsurface water to provide a condensing/heating source for the ground source heat pump. The LEED-NC v2.2 Reference Guide states that the credit intent is to ""limit or eliminate the use of potable water, or other natural surface or subsurface water resources available on or near the project site, for landscape irrigation."" This issue has also been addressed by CIRs dated 1/13/2003, 10/23/2001, and 6/9/2008. Applicable Internationally. " "None" "None" "X" "LEED Interpretation" "5195" "2009-04-08" "New Construction" "The project is a office building in Long island. We are planning to apply for credit WE 1.1. The project site is 2,295,612 SF. The planted areas on the site is 1,511,942 SF. A portion of this planted area will be left natural and the rest will include landscape design . We are planning to install irrigation in a 112,221 SF area planted with grass and shrubs. It is not clear to the design team which areas may be included in the calculation. Can we use all of 1,511,942 SF of planted area including the natural untouched areas to earn a point for this credit?" "A project may not include planted areas in the irrigation calculations if these areas are intended to be left in a natural state, and not therefore require irrigation. Only landscaped areas can be included in the calculations for this project. Please refer to LEED-NC v2.1 CIR ruling dated 3/23/2004 for additional guidance. Applicable Internationally. " "None" "None" "X" "LEED Interpretation" "2465" "2009-02-10" "New Construction" "Our project is a 120 bed hospital addition which includes 28 operating rooms, an expansion of the emergency department, a radiation/oncology department with 8 linear accelerators, and additional support functions. Some of the added spaces include process loads for instrument, cart, and equipment washing and sterilization which we know is to be excluded from the baseline and projected use calculations. The LEED-NC Reference Guide clearly address the usage of water for traditional functions of using water closets, hand washing related to the use of water closets or urinals, and showering. The Guide does not specifically address the usage of water at the multitude of other fixtures that occur throughout a hospital of a possible non-process nature. Due to the inherent nature of using surgical scrub sinks, flushing rim service sinks, housekeeping service sinks, and similar fixtures, the usage of water is more dependent on volume or a combination of volume and time used so identifying a savings, it there is one, is not practical and we would also place these fixtures into the category of process loads. What remains is a large number of sinks that are in exam rooms, patient rooms, and similar clinical spaces that are continuously used by staff for additional hand washing and would account for significant water usage and a corresponding reduction in usage if fitted with faucets that use less water than the base line 2.5 GPM allocated for lavatories and kitchen sinks. The Guide appears to be silent on applying usage factors to these types of fixtures so is it the intent for all of them to be considered process loads, or should we be developing a concept for usage that would permit calculating base line and reduced water usages towards a credit? Since the obvious goal is the real reduction in water usage, it would be appropriate to have a criteria that permits applying additional reductions to achieving a credit." "The applicant is requesting clarification regarding what water use fixtures may be considered process water use in a medical environment. Per several CIRs (3/9/2004, 7/8/2004, and 7/19/2005), all fixtures not regulated by the EPAct of 1992 are considered process water fixtures and are not to be included in calculations for WEc3. The EPAct of 1992 only regulates lavatory faucets, kitchen faucets, and metering faucets. Additionally, the LEED-NC v2.2 Submittal Template for WEc3 includes housekeeping service sinks. Therefore, flushing rim service sinks may be considered process water use fixtures." "730, 808, 1166, 5044, 5291, 100000916" "None" "LEED Interpretation" "5169" "2009-02-10" "New Construction" "Our project is a large 22,000 acre master plan located in Saudi Arabia. The entire master plan will not be seeking LEED Certification, however, the 4.5 million square foot University located within the master plan will be seeking LEED NC Multi-Building Certification. All condensate, gray water, black water and storm water from the entire Master Plan and the University is being collected and sent to a waste water treatment plant built for the Master Plan. The Waste Water Treatment Plant is designed to handle a daily flow of 9500 M^3/ day. The waste water is treated to tertiary standards. All the waste water from the plant is then used to provide irrigation for the Master Plan. The daily production of waste water is not large enough to handle all the irrigation needs of the master plan, however, through the reuse of this University waste water, the project is eliminating the use of potable water, or other natural surface or subsurface water resources, for specific portions of the master plan. We feel that this meets the intent of the Credit. The waste water plant output will provide all the irrigation needs for a nearby golf course, thereby eliminating the use of potable water for the golf course. This golf course uses the entire output from the waste water treatment plant. Implementing local water reuse treatment for each master plan building was a non-cost effective, non-efficient strategy. Waste Water reuse plants at a larger scale are more efficient for a development of this type. If the University landscaping consists of native plantings that allow for a 50% reduction in potable water use from the baseline, does this strategy allow for the University to achieve WE Credit 1.2: No potable water use?" "The CIR is inquiring whether the University project would achieve WE credits 1.1, 1.2 and 2 if wastewater from the site was treated to tertiary standards at an offsite Waste Water Treatment Facility (WWTF) and is then used to irrigate a golf course within the overall master plan community (but not within the LEED project boundary of the University). The WE credit 2 compliance path that this project is suggesting requires that wastewater be treated onsite to tertiary standards, which the project is not doing. While it is commendable that the project is treating contaminated water sources to tertiary standards offsite, the project cannot achieve WEc1.1 and 1.2 for the University project since the LEED project itself is not utilizing the treated wastewater. While certain campus credit compliance paths have been allowed in previous CIRs, please note that CIRs may not set precedent and are decided upon on an individual project basis. Campus approaches tend to apply to those projects incorporating sustainability practices campus-wide, but which are unable to document those practices on a individual project basis. If the project were to use water from the WWTF on the University campus for all irrigation purposes, and the water from this WWTF was conveyed specifically for non-potable uses, this would meet the requirement for one WEc1 credit. In addition to using only non-potable water for irrigation, if the University project can demonstrate a 50% reduction in total irrigation water consumption from a baseline case, it will be eligible to earn both WEc1.1 and WEc1.2. If the project can eliminate potable water use for all the landscape then project will comply with WEc1.2." "None" "None" "X" "Saudi Arabia" "LEED Interpretation" "5186" "2009-02-10" "New Construction, Core and Shell, Schools - New Construction" "This CIR seeks clarification on what fixtures and systems are covered in WE Credit 2. The credit specifically mentions water closets and urinals as fixtures for conveying building sewage. The subject project is a 35,000 sf office building for dentists and orthodontists. A typical office of this kind uses a water-intensive vacuum system for conveyance of human biological waste in the form of blood, saliva and mucous. A number of the doctors are considering using ""waterless"" vacuum systems that drastically cut the demand for potable water for purposes of conveying human biological waste. We seek guidance on the following: Should the fixtures that comprise a dentists\' vacuum system for wastewater (blackwater) conveyance be considered when calculating WE Credit 2." "The applicant is requesting clarification whether fixtures that comprise a dentists\' vacuum system for wastewater conveyance should be considered in the WEc2 calculations. Water use from dentists\' vacuum systems is considered process water use and is not eligible for consideration under WEc2 and WEc3. Previous CIRs dated 2/21/2007 and 3/9/2004 contain additional clarification regarding process water use. Note: this ruling does not apply to Core and Shell projects. Applicable Internationally. " "None" "None" "X" "LEED Interpretation" "2107" "2008-09-05" "New Construction, Schools - New Construction, Existing Buildings" "This project is seeking a ruling in regards to using the pond water on site for irrigation. The pond is feed by both storm water run-off and partially spring fed. The Owner wants to use the water (less than or equal to 50% of the amount of storm water dumped into the pond)to irrigate some of the vegetation on the property. The Owner will consult with the projects civil engineer to calculate this amount and we can submit if necessary." "The project would like to use a pond, which is fed by both stormwater and a spring, for on-site irrigation. The strategy of using an existing pond for stormwater management and irrigation provides many benefits including reduced stormwater management expenses and decreased use of potable water. In order to demonstrate credit compliance with WEc1.1, the project must demonstrate a 50% reduction in total water applied (TWA). As long as there is a 50% reduction, this credit will be earned regardless of the irrigation source. WEc1.2 provides an additional point when no potable water is used for irrigation. The definition of potable water for these purposes includes natural surface or subsurface water sources. However, WEc1.2 can be awarded provided the following three conditions are met: 1) The total volume of water drawn from the pond combined with the amount of water that is lost to infiltration and evaporation shall not exceed the amount of stormwater that enters the pond on a monthly basis. Document the stormwater coming in and going out (infiltration, evaporation & irrigation) on a monthly basis to confirm that the pond can meet the irrigation demand. If the pond cannot fill that need, the credit cannot be earned. 2) In every month of the year, the projected level of the pond shall not drop below historical average pond levels. 3) If there is a discharge out of the pond (into another water body), provide documentation that the removal of water from this pond does not compromise the integrity of the downstream water flow. Provide calculations to demonstrate compliance with each of the three conditions. Applicable Internationally. " "None" "None" "X" "LEED Interpretation" "2205" "2008-06-19" "New Construction, Existing Buildings, Core and Shell, Schools - New Construction" "The project is a renovation of a part of a student residence hall, which is part of a large university campus facilities program. Thus, drip irrigation is not proposed due to its higher maintenance requirements. The Reference Guide provides only two methods of irrigation in order to calculate efficiency: spray and drip. Spray irrigation is rated at 62.5% efficient while drip irrigation is rated at 90.0%. We feel there are more than just two options to calculate irrigation efficiency (IE) as it pertains to this credit. Not all at-grade irrigation equipment should be generalized as ""spray"" irrigation. There are fixed-arc spray heads, which have efficiencies as suggested by USGBC, and there are rotary heads that are more efficient. Rotary heads can provide a greater radius of coverage and dispense water at a lower precipitation rate. For the larger turf areas at this site, rotary heads provide higher uniformity. We can prove with credit submittal documentation that the IE of rotating sprinkler heads at a minimum is 75.0%. Rotary heads will not cover all turf areas; the remainder will have to be covered by fixed-arc spray heads. We are partitioning water consumption calculations in the design case by irrigation method and assigning the appropriate IE to each. Shrub areas are proposed with fixed-arc spray heads. The fixed-arc spray heads proposed have a pressure-regulating feature that reduces pressure at the nozzle to an optimum level. Fixed-arc spray head nozzles are designed to dispense a certain amount of water over a given area. A properly pressurized spray head and nozzle issues water droplets that are sized so as to not be affected by wind and sun and throw the proper distances. When pressure is too high, water droplets become finer (mist) and the spray patterns become distorted from slight breezes. This effect decreases efficiency, requiring longer irrigation times and more water to be dispensed in order to obtain the proper net result. Not all heads have the pressure-regulating feature. Heads that do contain this feature regulate pressure to their optimum of 30 psi. 60-psi pressure at the spray heads is available. Per the manufacturer\'s data (to be submitted), water consumption with pressure regulation is 71.0% of standard fixed-arc designs. Rotary heads do not have this feature and require the full 60-psi available. Irrigation controls are intended to automatically adjust watering times based on local climate conditions. Conventional controllers are set to turn irrigation on at the same time everyday for the same duration. The campus utilizes a central control system with weather station to manage irrigation duration. Evapotranspiration (ET)-based controllers receive central control signals and adjust irrigation times based on daily weather. Rain sensors enhance water savings further by suspending the daily irrigation cycle depending on how intense rainstorms are. The irrigation engineer calculates that an ET-based controller dispenses only 61.1% of the water used by a system with typical controls in the month of July at our location (to be submitted). In the spirit of controller efficiencies as suggested in the Reference Manual, we request that the USGBC allow us to expand the credit calculation analysis to include the efficiencies and reductions expected by specifying rotating heads, pressure-regulating heads, and ET-based controlling. Our project will have at least a 53.6% reduction in potable water consumption during the month of July compared to typical irrigation system with the same landscaping scheme." "The project is requesting clarification on whether or not efficiencies other than those associated with spray and drip irrigation heads (0.625 and 0.9 respectively) can be used in the calculations to determine total water applied. The use of alternate efficiencies for different types of irrigation heads is acceptable. However, similar to the percent reduction in water use attributed to ET-based controllers, the reported efficiencies of alternate irrigation head types must be supported by manufacturer documentation or detailed calculations by the landscape designer or irrigation engineer. The supporting calculations for the design irrigation head efficiency cannot simply be based on a comparison to the usage rate seen in a less efficient standard or baseline irrigation head as suggested by the CIR. The reported efficiency of any irrigation head type must be a measure of the amount of water that actually reaches and is used by the plant materials and must address both evaporation and drift losses. ET-based controllers are already accounted for in Equation 3 as detailed on page 121 of the LEED-NC v2.2 Reference Guide. Further, the percent reduction in water use attributed to any weather-based controller or moisture sensor-based systems must be supported by manufacturer documentation and detailed calculations by the landscape designer or irrigation engineer. Partitioning the project into areas by irrigation type is acceptable. However this does not exempt the project from demonstrating compliance with the water use calculation methods detailed in the Reference Guide. For example, the areas that are partitioned by irrigation type must obviously also take into account sub-areas with specific plant types, microclimates and densities. These sub-areas will have distinct evapotranspiration rates which should be calculated using the appropriate landscape coefficient (KL) for that area. Applicable Internationally. " "None" "None" "X" "LEED Interpretation" "2207" "2008-06-19" "New Construction" "Our project includes a college dormitory in eastern Washington, a climate with summer droughts. Significant areas will be densely planted with drought tolerant native plants, and a the project includes a small lawn. Reclaimed roof water will be used to irrigate the lawn. At the native planting areas most likely to be impacted by humans, larger installation sizes are planned, requiring more than one year of irrigation, so a permanent but seldom used system will be installed, mostly just to establish plants. At several other areas, plants will be installed at small enough sizes to allow establishment using temporary irrigation for one year. We have reviewed relevant CIRs related to temporary irrigation and have the following questions: QUESTION #1: Do the following meet the requirements for removal of temporary irrigation after one year?  Contractor will be required as part of the contract to remove all temporary irrigation zones at end of one year, including all pipes, valves and sprinklers.  Owner will also certify in writing that temporary system will be removed. QUESTION #2: Do the following installation techniques meet the requirements for temporary irrigation?  All PVC pipes and valves will be pinned directly to the surface of soil.  Sprinkler bodies will be buried, but immediately attached to pipes on the surface. RATIONALE FOR THE ABOVE PROPOSED TEMPORARY IRRIGATION SYTEM:  System will be drained during winter (November to April), thus no soil cover is needed.  Surface piping is less likely to be retained after establishment than underground systems, because of undesirable appearance.  Surface piping causes less disturbance to remove than drip tubing because there are so few pipes involved.  Large radius spray heads/rotors will be used, because they can be spaced widely, resulting in a bare minimum of piping and quantity of sprinkler heads.  Due to high density of our plantings, drip irrigation would require much more total material to irrigate all plants, would be more difficult to remove, and would cause more disturbance to planting areas at removal. For example, one large planting area will contain native plants spaced 16"" apart, with seed applied between. A large quantity of dripline would be required to irrigate this, and disturbance would be significant at removal.  Pop-ups will be used (vs. fixed, rigid risers), to protect from vandalism -- heads will be tucked into soil, disappearing from sight when not in operation, even though attached immediately to surface mounted pipes. Vandalism is a significant problem on this college campus. The university does not want the liability of above ground spray heads attached to stakes and the danger that can pose to careless students. QUESTION #3: Would any of the options below also meet the requirements for temporary irrigation?  Covering mainline and lateral lines with mulch to help prevent vandalism.  OR Painting surface mounted pipes a dark color, to help prevent vandalism.  Burying mainlines but not laterals lines. At end of one year, laterals would be removed, but mainlines remain so that quick couplers may be used later for hand watering during periods of extended drought." "The project would like to permanently bury the mainline of a temporary irrigation system and remove the rest of the irrigation system within one year of installation. The mainline would remain in place so that quick couplers could be used for hand watering. Although the applicant is proposing to only remove a portion of the irrigation system, the portions that will be removed can be removed easily and this removal will then completely disable the automated irrigation system. Therefore, this strategy meets the intent of the requirement. The mulch covering and the pipe color do not affect this ruling. Please provide a letter from the owner verifying that the entire system, with the exception of the main lines, can be easily removed and will be removed within one year. A contract for removal is not necessary although it would be desirable. Applicable Internationally. " "2552, 100000343, 100000345, 100000346" "None" "X" "LEED Interpretation" "2163" "2008-06-09" "New Construction, Existing Buildings, Core and Shell, Schools - New Construction" "This question is regarding the applicability of a process water re-use and treatment system for WE credits 1.1-3.2. Our coastal project is proposing the use of a ground-coupled open-loop heat rejection system with a side-stream desalination plant. The system draws non-potable brackish water from the ground, rejects heat from cogeneration and HVAC systems into the water and returns the rejected process water to the ground. The water is not potable source water (e.g. sourced from potable watersheds such as lakes and rivers) and stringent environmental regulations are in place with regard to pumping rates / volume, and quality of the return water. Approximately 10% of the rejected process water flow is diverted for re-use in the building. The diverted water is treated using a reverse osmosis desalination system. The treated water will be used onsite for irrigation and conveyance. Benefits of this system include a reduced impact on the already taxed local potable water supply, reliability of water source, and environmental benefit due to on site treatment and re-use. We believe we should be able to take credit for the municipal water savings resulting from this system, provided that energy use from the system is included in energy calculations. Please provide guidance for credit applicability." "The applicant is inquiring as to acceptability of a process water re-use and treatment system for WE credits. In previous CIRs, recycled on-site water (such as water from a cooling tower) has been accepted for credit compliance. However, in this case, the portion of brackish water not returning to the ground from the ground-coupled open loop rejection system, which would be diverted for re-use on site, can not be used as is. Before this water could be put to any use, it would require going through Reverse Osmosis (RO) treatment which is an energy intensive process. The applicant is correct in suggesting that using this water would reduce/eliminate the need to use municipal potable water for landscape irrigation. In order to take credit for using non-potable water the energy use to desalinate the water must also be included in the EAc1 calculations. In addition, it should be noted that the intent of this credit is to encourage water efficient or xeriscape landscaping practices, which require little to no irrigation and/or use no potable water for irrigation. Hence, the project team should be ready to document the overall approach towards meeting the intent of the credit. Applicable Internationally. " "li-10284, 10284" "None" "X" "LEED Interpretation" "2089" "2008-04-14" "New Construction" "Our project is a 9 million SF Graduate University located in Saudi Arabia dedicated to the research of alternative fuels and renewable energy. The campus will consist of research labs, lab support areas, administration buildings, a library, a commons building, food service, an auditorium, conference rooms, lecture halls, offices and public areas. We will be seeking LEED NC Multi-Building / Campus Certification. An adjacent residential area is planned as part of the Master Plan, but will not be included in our LEED boundary for obvious LEED Certification system conflicts. The Campus will utilize efficient fixtures to reduce waste water conveyance and potable water use by 42%, shy of the 50% requirement for fixtures. All the remaining gray water and black water from the Campus is being collected and sent to a new local waste water treatment plant just outside of the LEED boundary for the Campus. The WWTP is being constructed as a local treatment system for the Campus and the surrounding residential areas, but is located just outside of the Campus LEED boundary. This WWTP is being constructed in close proximity to the Campus and residential area to avoid the extension of existing infrastructure. We are seeking compliance through Option #2 for this Credit: Treat 50% (100% for an Innovation in Design Point) of wastewater on-site to tertiary standards. Treated water must be infiltrated or used on-site. Although the WWTP is just outside our LEED boundary for Master Plan reasons, the intent of treating the Campus water and infiltrating it on-site is being met. The water is treated to tertiary standards at the WWTP and is then piped back to the Campus for all irrigation purposes. The Campus will use 100% recycled water from the WWTP for all irrigation needs and per the intent of the Credit, this will ""increase the local aquifer recharge."" The Campus will discharge 29,215,330 liters of water annually to the WWTP. 84,479,311 liters, from the Campus and the residential area will be treated and returned to the Campus boundary and infiltrated on-site as irrigation. Therefore, 100% of the waste water being generated within the project boundary is being treated to tertiary standards and infiltrated on-site, which in turn, increases the local aquifer recharge. Please advise if the project strategy meets the intent of the Credit." "The project team is inquiring as to whether or not they can use water treated to a tertiary standard from a wastewater treatment plant located just off-site of their campus to achieve potable water savings for wastewater use. Yes, the project can achieve this credit by using non-potable water from either on-site or municipally treated wastewater as stated in the LEED NCv2.2 Reference Guide. The water being used for this would need to be considered ""reclaimed water"", so therefore the term ""tertiary standards"" indicated in your request would need to be qualified with data showing that it meets the requirements stated in the LEED NCv2.2 Reference Guide defining Tertiary Treatment as; ""the highest form of wastewater treatment that includes the removal of nutrients, organic and solid material, along with biological or chemical polishing (generally to effluent limits of 10 mg/L BOD? and 10 mg/L TSS)"", but would not be considered potable or drinking quality water. The plant itself can be considered a municipal treatment plant. All other terms, conditions and requirements of the credit would need to be met upon submittal. Please note that gray water is not and does not come from any sewer wastewater treatment plant. Gray water by definition is raw, fresh, unfiltered, wastewater from specific human activities using potable water that does not and has not been in contact with black water or a toilet or urinal fixture. Applicable Internationally. " "None" "None" "X" "LEED Interpretation" "2044" "2008-02-29" "New Construction" "This CIR describes our methodology for developing baseline and design water use for a LEED NCv2.2 project. This project includes one existing, renovated building with a large new addition. It will be occupied by the General Assembly and will include committee rooms for internal or public meetings, offices, press room, cafeteria. The general assembly is only in session for 4 months, which is when the highest occupancy will occur. The other 8 months will be a reduced count. First we have determined the average building occupancy based on visitors and full/part time staff in session and out of session per the following assumptions 1) In session: a) New addition Offices will be used 100% during session at 100% capacity. The number of regular building occupants is based on desk count per the preliminary drawings. The four large committee rooms will be used 100% during session at 100% capacity. There will be 30 elected officials (building occupants already accounted for in the number of regular building occupants) and the rest visitors. Meeting rooms and small committee rooms will be used only for internal meetings. Single occupant toilets adjacent to the large committee rooms will be used during session only by committee members. Other employees and visitors will use the core toilets. b) Existing building Offices will be used 100% during session at 100% capacity. The number of regular building occupants is based on desk count per the preliminary drawings. The ballroom will be used 100% during session at 100% capacity. There will be 30 elected officials (building occupants already accounted for in the number of regular building occupants) and the rest visitors. Journalists will be using the pressroom only during session, approx. 2hours per day. Meeting rooms and small committee rooms will be used for internal meetings. Single occupant toilets adjacent to the ballroom will be used during session only by committee members. Other employees and visitors will use the core toilets. 2) Off session: a) New addition Offices will be used 50% of the time off session at 10% capacity. The four large committee rooms will be used 50% of the time off session, with 50% capacity. We assume 3/4 building occupants, 1/4 visitors. Meeting rooms and small committee rooms will be used for internal meetings. Employees and visitors will use the core toilets. b) Existing building Offices will be used 50% of the time off session at 25% capacity. The ballroom will be not used off session. Meeting rooms and small committee rooms will be used for internal meetings. Employees and visitors will use the core toilets We have differentiated use of core toilets and single occupant toilets because two different flush rates are applied. Single occupant toilets are low-flow single flush (1.3 gpf) while the core toilets are dual-flush (1.1/1.6 gpf). We have multiplied the full-time equivalent building occupants and visitors during session by 1/3 and out of session by 2/3 to finally get the aggregate total FTE occupants and visitors for WEc3. We have considered the peak FTE occupants and visitors during session to calculate the minimum number of secured bicycle racks and showers to comply with SSc4.2. Please advise if this methodology is acceptable." "The CIR is requesting verification that the presented method of calculating FTE occupants is acceptable. In general this approach seems reasonable for what is a relatively complex occupancy pattern. When this project is submitted for review, be sure to include an explanation with at least this level of detail. It would also be beneficial to explain if the single occupancy restrooms are only accessible by certain users (i.e. key access) or if the assumption was that only certain occupants would be likely to use them. Please note that the LEED Submittal Template allows for the applicant to input a custom occupancy type (in addition to the standard FTE/Student/Vistior/etc. categories. This may allow for a simpler calculation than trying to lump together multiple occupancy types to create a single FTE value. The water savings of dual flush toilets in commercial and public settings has not yet been proven; there is a need to verify that dual flush toilets are in fact used as intended by consumers, and further research is necessary." "None" "None" "LEED Interpretation" "2007" "2008-02-05" "New Construction" "The subject property of this CIR is a new, 135,000 SF, 140-unit, mixed-use residential building on a previously developed infill site. The project targets a minimum 40% water use reduction and has purposefully selected low-flow fixtures as the primary means to achieve this goal. The kitchen sink fixture is the focus of this CIR. The kitchen sink selected for the residential units was chosen for its low-flow performance, cost, ease of installation and compatibility with the unit design. The sink comes equipped with a flow rate limiter that can be adjusted to reduce the flow rate by 50%. The maximum flow rate is 2.5 gpm so, once adjusted, the flow will be reduced to 1.25 gpm. The product cut sheet provides detailed, step-by-step instructions and a diagram on how to make this adjustment. The adjustment requires removal of the sink lever and fixing screw and use of an allen wrench to adjust an internal screw, so it is highly unlikely that tenants would override any adjustment made during initial installation. This adjustment will be sufficient to exceed the overall project goal of minimum 40% water use reduction when coupled with the other selected low-flow fixtures. The architect and owner have mandated that the kitchen sink flow rate is adjusted to the minimum in each of the units during installation to reduce water use and earn an innovation point for exemplary performance of WEc3. To ensure that this flow-rate is realized, the architect will integrate these instructions, plus the product cutsheet, into Part 3 (""Execution"") of Division 15 (""Mechanical"") of the project specifications (we can send the USGBC the cutsheet to faciliate review if desired). As the project\'s LEED consultant, we will also review this requirement and installation procedure at our scheduled contractor kickoff meeting, which will take place prior to the start of construction. Lastly, if the USGBC desires, the owner may provide a written commitment to verify that the adjustment was made through post-installation sampling and to provide corrective measures if the sampling fails. Are these mechanisms sufficient to verify to the USGBC that the kitchen sinks will perform at 1.25 gpm, rather than 2.5 gpm, and to enable this performance as the entry in the WEc3 LEED-NC 2.2 Submittal Template? If so, what documentation is required in addition to the product cutsheet to supplement the LEED Submittal Template?" "The method described to document water-flow restrictors is in general appropriate, however, in this case, the WE TAG does not feel that this strategy is worthy of an innovation credit for exemplary performance beyond WEc3. Kitchen sink faucets are used to fill pots among other things. Expecting tenants to use 1.25 gpm faucet flows to fill pots will cause frustration and lead to tenant attempts to readjust to higher flow rates. Earning LEED points should not result in dissatisfaction and frustration which will reflect back on the LEED product. It is strongly recommend to keep the kitchen faucets at 2.5 gpm and to use alternate strategies., such as foot pedal operated faucets to reduce water use without causing dissatisfaction." "None" "None" "LEED Interpretation" "1979" "2008-01-31" "New Construction" "Credit Interpretation Request regarding: Re-use of nuisance ground water flows for the benefit of WE Credit 1.2: Water Efficient Landscaping-No Potable Water Use and WE Credit 2: Innovative Wastewater Technologies " "The applicant is inquiring whether groundwater, which needs to be collected and pumped from the exterior of the foundation, can be used for irrigation to achieve both points for WEc1.1 and WEc1.2. This use would comply with the intent of the credit, as long as the pump only draws water from the immediate vicinity of the slab and foundation. The applicant intends to pump the groundwater to a cistern, which also serves the function of collecting stormwater. Include with the LEED submission calculations to show that the cistern has the capacity to serve the relevant stormwater management functions as well as meet the irrigation demands in July. The calculations need to allow for the drawdown of the cistern between storm events for the design storage volume to be available. Applicable Internationally. " "None" "None" "X" "LEED Interpretation" "5291" "2008-01-31" "New Construction" "This project is a co-op supermarket which contains food processing areas. According to the Energy Policy Act of 1992 (EPAct), calculations are based on estimated occupant usage and shall include only the following fixtures (as applicable to the buildings): water closets, urinals, lavatory faucets, showers and kitchen sinks. We will include the following fixtures in our calculation: --All water closets, urinals, lavatory faucets, break room/community room sinks, janitorial sinks and hand washing sinks. Per our understanding of the EPAct and this credit, it is appropriate to exclude process water from our calculations. Specifically, our process water includes: --Food processing sinks where water is used to rinse dirt and bacteria off fresh produce and meat/seafood. --Sanitation sinks where water is used for sanitary clean-up of utensils, trays and cutting boards. This consists of a 3 bay sink where one sink is filled for soapy water, one filled for rinsing and one for sanitation. The faucets for these sinks are only run for the purpose of filling these bays and are not in use continually. Additionally, it is our understanding that process water includes the following: --Drinking fountains, filtered water for resale through kiosk, ice maker, water for the coffee machines, dishwashers, till kettle (used for making soup), produce misting hose, and other fixtures and equipment that use water principally for preparing food for sale. Please confirm that we are correct in excluding the process water items listed above from our calculations. While the project is registered under the 2.1 rating system, we are upgrading this credit to version 2.2, so please address it in the context of that version\'s requirements." "Yes, fixtures used for process water uses are beyond the scope of the Energy Policy Act of 1992 and are to be excluded from the water use reduction calculations for LEED-NC v2.1 and LEED-NC v2.2. Applicable Internationally. " "730, 808, 1166, 2465, 5044, 100000916" "None" "X" "LEED Interpretation" "1974" "2007-12-13" "New Construction" "Our project is a 9 million SF Graduate University located in Saudi Arabia dedicated to the research of alternative fuels and renewable energy. The entire campus will be New Construction on a Greenfield site and will consist of research labs, lab support areas, administration buildings, a library, a commons building, food service, an auditorium, conference rooms, lecture halls, offices and public areas. All condensate, gray water, black water and storm water from the Campus is being collected and sent to a waste water treatment plant off-site and outside of the project boundary. The water goes through the following process and is then used to irrigate a nearby golf course: WWTP A. Introduction WWTP is an advanced WWTP that is designed to treat an average daily sewage flow of 9500 M3/d. B .Processes used in the design of the WWTP. The Processes used designs are: 1. Fine screen, 2mm. 2. Grit removal system. 3. In line equalization tanks. 4. Anoxic reactor. 5. Aeration tanks. 6. MBR Tanks (KUBOTA membrane is used) 7. Effluent Tanks. 8. Centrifuge dewatering system. 9. Chemical dosing units. 10. Emergency storage ponds. C. Very high effluent quality produced The effluent quality produced form the WWTP is as follow: BOD = 10 mg/L S.S = 10mg/L NH3 = 1.0mg/L TKN = 2.0mg/L The effluent produced will be used to irrigate the Golf coarse area. Through the reuse of this Campus waste water, the project is eliminating the use of potable water, or other natural surface or subsurface water resources available on or near the project site for landscaping irrigation of an adjacent site. The interpretation needed is twofold: Would this process result in a gray water effluent that in keeping with the Credit Intent, would comply with this Credit by irrigating a nearby site? And if the irrigation of a nearby site is not acceptable, would the project comply if effluent water from the WWTP was piped back to the campus for all irrigation purposes?" "The CIR is inquiring whether their contribution to an off-site wastewater treatment plant (WWTP), which provides non-potable water for irrigation of a nearby site, would comply with the credit. In addition, the applicant inquires whether using water from this plant on site for all irrigation would comply with the credit requirements. Contributing condensate, gray, black, and storm water to the off-site WWTP would not be enough to earn WEc1. This strategy, while positive, does not adequately address the intent of the credit to limit or eliminate the use of potable water resources for landscape irrigation. Contributing to a non-potable source does not necessary encourage its use. The fact that this water may be used by a nearby golf course does not figure into the decision. If the project were to use water from the WWTP on the campus for all irrigation purposes, and the water from this WWTP was conveyed specifically for non-potable uses, this would meet the requirement for one WEc1 credit. It should be noted that, in addition to using only non-potable water for irrigation, the project must demonstrate a 50% reduction in total irrigation water consumption from a baseline case in order to earn both WEc1.1 and WEc1.2. Applicable Internationally; Saudi Arabia " "None" "None" "X" "Saudi Arabia" "LEED Interpretation" "5095" "2007-12-13" "New Construction" "Our LEED NC v2.2 registered project includes additions and major renovations to an existing office/laboratory building. We wish to pursue WEc2 - Innovative Wastewater Technologies on the project and would like to know if our strategy for compliance is acceptable in pursuit of OPTION 1. Within the new additions, we plan to install high-efficiency fixtures including high efficiency dual flush and low flow water closets and urinals for all new addition flush fixtures to contribute towards wastewater reduction. Within the existing building, the flush water closet fixtures are 3.5 gallons/flush rated and the urinals are 1.5 gallons/flush rated. We plan to replace a combination of the water closet fixtures with high efficiency low flow type and upgrade the urinal flush valves with new, high efficiency low flow type to reduce the sanitary discharge. The combination of new addition fixtures and modifications to the existing fixtures will reduce the total site sewage conveyance by greater than 50% below the current sewage conveyance of conventional fixture standards in the new buildings and no modifications to the existing fixtures. However, this credit references the Energy Policy Act of 1992 baseline water quantity flow requirements. We would like to use the gallons/flush ratings of the existing water closets and urinals as the baseline discharge for the existing fixtures in our calculations for WEc2 - Innovative Wastewater Technologies. We believe we are meeting the intent of the credit by significantly reducing the generation of wastewater and the potable water demand." "No, existing fixtures cannot be used as the baseline for calculations for WEc2. For LEED calculations, the baseline case is defined as the building with fixtures that meet the Energy Policy Act requirements, NOT the actual fixtures existing prior to retrofit. The design case is defined as the building with the actual fixtures installed. This ensures that there is a consistent baseline across all LEED projects. Please refer to the LEED calculation methodology under WEc2 in the LEED-NC v2.2 Reference Guide and LEED-NC v2.1 WEc3 CIR ruling dated 4/19/2004 for additional information and guidance. Applicable Internationally. " "None" "None" "X" "LEED Interpretation" "1866" "2007-12-03" "New Construction" "It is unclear whether it is the intent of this credit to include commercial kitchen sinks in the calculations. While the reference guide states, ""Calculations are based on estimated occupant usage and shall include only the following fixtures: water closets, urinals, lavatory faucets, showers and kitchen sinks,"" the definition of ""kitchen sink"" is a bit unclear. Our hospital project includes a commercial kitchen and dining room to serve the entire hospital population. There are two kinds of sinks in this commercial kitchen: hand sinks primarily used for hand washing, and commercial sinks used in the preparation of food. We believe that the hand sinks within the kitchen clearly fall within the fixture group that is to be used in this calculation. Our question lies with the commercial sinks and whether or not they should be included in the calculation. Our initial interpretation is that the commercial sinks in the kitchen are used for process loads: filling pots, washing vegetables, etc. We came to this conclusion partially based on a credit interpretation ruling dated 3/9/2004, ""Process water includes, but is not limited to, water use from cooling towers, dishwashers and clothes washers."" Process water fixtures and equipment are not included in the calculation for this credit, therefore our understanding is that we should not include the commercial kitchen sinks in this calculation. We found further guidance on this decision by looking at Table 2 on page 141 of the LEED for New Construction Version 2.2 Reference Guide. This table titled, ""Standard Fixture Uses by Occupancy Type"" states that for a non-residential kitchen sink, the usage is 1-15 second duration from each FTE per day. While this is a reasonable estimate for each of the hand sinks, the commercial sinks are likely to be used for much longer periods of time to, for example, fill a pot or rinse vegetables. Please advise on our initial interpretation that the commercial sinks are process load fixtures." "The inquiry is asking if process water fixtures and equipment (such as commercial kitchen sinks) should be excluded from the calculations for WEc3. The project team\'s interpretation is correct - commercial sinks are considered process loads and are not included in the water use calculations for WEc3. WE TAG recommends that the applicant consider use of a special use pot filler in addition to the regular use faucet at 2.2 and 60 psi, as commercial sinks are not process water in the same sense as cooling towers and commercial dishwashers. Applicable Internationally. " "100000916" "None" "X" "LEED Interpretation" "1923" "2007-10-22" "New Construction, Core and Shell, Schools - New Construction" "The project has a subterranean parking garage for 49 vehicles (19,247 sqft) that is within a mile of the Napa River. With this close proximity to the river and a high water table, the parking garage has ground water infiltration that is being pumped out at 1000 gallons per day. The captured ground water is being filtered (e.g. motor oil, fuels, paints/stains and solvents, asphalt products, concrete, herbicides, pesticides, and TSS, etc.) and pumped out of the garage to the city storm drain system, according to city code and San Francisco Bay Area Storm Water Management Agency Standards. The question is, could this captured ground water be used in the building as graywater for flushing toilets and urinals to offset potable water use and thereby qualify for LEED NC v2.2 Water Efficiency credits?" "The applicant is proposing to use groundwater that has been pumped to prevent flooding to reduce potable water demand by using it for flushing toilets and urinals for WEc2. This strategy is acceptable as long as the water is only being pumped to keep the building dry; sinking a well or pumping more water than is necessary are not acceptable strategies. If the water that the project team is using is water that would be produced and discharged anyway, then the project team may use include the reused water in the calculations for the credit. The water quality of the water being used in toilets and urinals should be addressed in cases of recycled water that is untreated or minimally treated. States and regulatory agencies tend to require the water to be up to potable water standards before it goes into the toilet or sink. Note that the water quality should meet local standards and consult manufacturer recommendations for compatibility of parts with greywater use. As a point of clarification, captured groundwater is different than greywater; the term should be changed to alternate on site water sources in this CIR. Applicable Internationally. " "None" "None" "X" "LEED Interpretation" "5062" "2007-07-12" "New Construction" "Municipally provided recycled water is available to the project site and the intent of the irrigation design is to use this recycled water to the fullest extent possible. A portion of the park will be a swimming pool/aquatics complex. The San Diego County Department of Environmental Health (DEH) does not permit the use of recycled water for irrigation within pool areas due to health concerns regarding cross contamination of potable water systems as stipulated in the San Diego County Rules and Regulations for Recycled Water Use. Therefore we are required by DEH to use potable water for the irrigation within the pool complex. The total irrigated landscape area within the park limits is 786,877 SF. Of that, 756,210 SF will utilize recycled water and 30,667 SF (pool area) will utilize potable water. This equates to over 96% of the total site utilizing recycled water. Every effort has been made to use recycled water to the fullest extent possible while remaining in compliance with local codes and regulations. Please confirm that this approach, which utilizes 100% reclaimed water in all areas allowed by code, will achieve this credit." "The project is inquiring whether it may achieve both Water Efficiency credits for the use of municipally-provided reclaimed water for irrigation purposes despite the fact that certain areas of the project utilize potable water for irrigation. Although this credit indicates that projects must use 100% reclaimed water for all project irrigation purposes, it is permissible for this project, in this circumstance, to exclude the areas nearest the swimming pool as reclaimed water may prove to be a public health hazard. For project Submittal, the team should be prepared to provide documentation from the San Diego County DEH demonstrating the code requirement." "None" "None" "LEED Interpretation" "1709" "2007-03-22" "New Construction" "This Arizona project has landscaped exclusively with xeriscape materials. The local zoning authority requires an automated irrigation system and will not issue a building permit without one. Our intention is to use no potable water, via the mandated drip irrigation system, except during the plant establishment period and after that only in case of extreme drought where precipitation falls below ""normal"" anticipated rainfall (e.g. between 10/18/2005 and 03/11/2006 we experienced 144 continuous days of no precipitation-a period that averages 3.58""). We will install a dedicated water meter on the irrigation system and will log quarterly water meter readings and local precipitation records to verify the performance of the intent. The 8/16/2005 Ruling states, ""WEc1.2 may be achieved (by)demonstrating that the quantity of \'normal\' anticipated rainfall meets 100% of your irrigation needs ... ,providing potable water as a backup is acceptable"". We have met the credit intent with our xeriscape landscape palette, as well as provided a method of verification of continued performance via data logging. Since a permanent irrigation system is mandated by zoning, it would be onerous and wasteful to spend money, time and resources to design and build a parallel captured rainwater or recycled water system. We cannot eliminate the permanent irrigation system due to zoning restrictions, and since our intent is to only use it to supply potable water for establishing plantings and as a drought backup, we believe we have met the full intent of the credit." "The project is inquiring if it is possible to achieve WEc1.2 despite the installation of a permanent irrigation system which is required by the local zoning authority in Arizona. The project\'s xeriscape landscaping, as described, would only need to be watered for initial plant establishment and in times of drought. Per CIR Ruling 4/4/2005, it is acceptable for projects to provide potable water as backup irrigation during extended dry periods. Since a permanent irrigation system was installed only to comply with the local zoning authority and not for on-going landscape irrigation, the project is eligible to achieve WEc1.2. For appropriate documentation, please be prepared to provide a listing of the xeriscape plants incorporated into the site landscape, their water needs, and the monthly average rainfall for the project\'s location. The project should also provide evidence of the local zoning authority\'s requirement to install a permanent irrigation system. Note: This interpretation is specific to your project description and does not establish precedent that other projects with permanent irrigation systems will be acceptable for achievement of WEc1.2." "None" "None" "LEED Interpretation" "5044" "2007-03-22" "New Construction" "Our project is a full service car dealership that includes a staff operated car wash. The proposed design will utilize a closed-loop recycled car wash system that will reduce the amount of potable water required to wash a vehicle from 25 gallons to 6 gallons as compared to a conventional car wash system. A conventional carwash system uses 25 gallons of potable water that is 100% evacuated to the sanitary sewer. The proposed design will utilize 25 gallons of reclaimed water from reclaim holding tanks for the soap and wash process and only 6 gallons of potable water for the final rinse. (Note: the proposed system is the most efficient technology currently available). It is our position that carwashes are an integral part and a standard component in automotive dealerships. Additionally, car washes are the largest consumers of potable water in automotive dealerships and as such should be considered in the calculations for this project. This request is to confirm that the water efficient car wash equipment system can be considered towards Innovative Waste Water Technology which sites "" water conserving fixtures (water closets, urinals)"" as being the fixtures allowed to be considered under this point." "The project is inquiring if it is possible to achieve WEc2 through the use of a water efficient car wash system. WEc2 deals with water-use reduction as it relates to sewage conveyance, thus it doesn\'t pertain to this request. The project\'s petition is more appropriately suited for an Innovation in Design (ID) point for process water use reduction. As indicated in CIR Ruling 8/31/2004, a project may be eligible for an ID point for reducing process water if a whole building approach is used (dish washers, drinking fountains, cooling towers, etc., in addition to the car wash). The project will need to demonstrate a 10% savings in process water use as compared against the regulated water use calculated in WEc3. Please refer to CIR Ruling 8/31/2004 for details on how the project should document this credit. Applicable Internationally. " "730, 808, 1166, 2465, 5291, 100000916" "None" "X" "LEED Interpretation" "1681" "2007-02-26" "New Construction" "We have assumed a 50%-50% calculation for men\'s restroom for the following reasons: The use of the facility is retail therefore we anticipate more users in the restroom at one time when compared to a similar size facility for office use. The bulk of the users are transient with a temporary use of the restroom mainly for liquid waste versus solid waste. This increases the chances for the low flow water closet to be used more often for liquid waste. On Table 2.1 of the LEED-NC form indicated the use of ""Dual-Flush"" water closet to be at 50% (solids) for male and 50% for non-water urinal. Using this approach, we\'ll save 51.3% of water. This approach may not be realistic in terms of the daily usage of the plumbing fixtures as being 50/50, but this will be the worst case scenario. In reality, urinals will be used more often compare to toilets, more like 60%-70% more than the toilets. In the event when urinals are going to be used 100%, the dual-flush toilets will be used for liquid waste and still conserve water due to the low-flow of 0.8 gpf which is not shown as an alternate factor in the LEED form Table 2.1 Design Case." "For the purposes of LEED water use calculations, modifications such as a change to the male/female ratio, or daily use per person, or frequency of use of fixture types can be made provided clear justification is provided, with all assumptions noted in the LEED submission and corresponding calculations. Applicable Internationally." "None" "None" "X" "LEED Interpretation" "1655" "2007-02-21" "New Construction" "Our LEED v2.1 project is a 20,000 square foot nanotorium built as an addition to an existing community center. We wish to pursue WEc2 - Innovative Wastewater Technologies on this project and would like to know if our strategy for compliance is acceptable. On this project, use of a standard pool filtration system would produce 11,000 gallons of backwash water per week. Backwash water is run in reverse through pool filters for cleaning. Although backwash water is not used for sewage conveyance, local code requires that is discharged through the sanitary sewer line. On this project, we are installing an advanced filtration system which will reduce the volume of backwash water to 800 gallons per week. This will result in a weekly savings of 10,200 gallons of potable water (over 500,000 gallons of water per year). Along with additional water saving strategies that will be included on this project (waterless urinals, low-flow fixtures), the total volume of potable water being discharged to the sanitary sewer line will be reduced from a baseline of 20,000 gallons per week to 7,400 gallons - a reduction of 63%. We would like to know if we can include the pool backwash water savings in our calculations for WEc2 - Innovative Wastewater Technologies. We believe we are meeting the intent of the credit by significantly reducing the generation of wastewater and the potable water demand." "As noted under CIR ruling dated 3/9/2004, process water use is not eligible for consideration under WEc2 or WEc3. However, the optimization of process water use is eligible for LEED credit under the Innovation in Design category. Please see IDc1.1 CIR rulings dated 8/31/2004 and 5/13/2005 for guidance on attempting this as an innovation credit. Applicable Internationally." "None" "None" "X" "LEED Interpretation" "5033" "2007-02-12" "New Construction, Schools - New Construction" "We are currently designing a new County Justice Center. The project consists of 193,338 gsf and will house the county jail, Courts and office space for the County Attorney, Community Corrections, Sheriff and Court Administration. The facility comprises an occupant load of 1,879 - 587 of which are attributable to the jail portion of the facility including the inmate population, staff and visitors. During the design development process, the project team has determined that the project will be able to achieve over 40% water efficiency for the project in the courts and office space of the project. However, due to the product availability, maintenance requirements and the behavioral nature of the inmate population we have determined that the project will be unable to use low flow fixtures for the jail portion of the building. Use of low flow fixtures will place an unreasonable burden on the construction project and negatively impact the ongoing operations and maintenance of the project. Not being able to use these fixture types will negate the water efficiency achieved in other portions of the building. We respectfully request that the jail portion of the facility be exempt from the water efficiency calculations and that these strategies be applied only to the Courts and Offices areas of the project." "In the definitions section of EPAct 1992 (Section 123, B) ""water closet"" and ""urinal"" fixtures installed in prisons are excluded. Also, the definition of ""showerhead"" excludes safety showerheads. Thus, these fixtures do not fall in the scope of this credit, and do not need to be included in the calculations for WEc3. Applicable Internationally.\n\n***This LI has been overturned by LI 10120, for projects registered after 11/1/2011, and LI 10216, for projects registered after 7/1/2012\n\n***Update 1/1/13: This LI has been made applicable to LEED NC v2.0, v2.2, and Schools v2007." "10120, 10216, 100000754, 10215" "None" "X" "LEED Interpretation" "1621" "2006-12-11" "New Construction" "Our project is a student recreation center in an urban location. We have proposed a rainwater harvesting system that will collect roof and site stormwater to be stored in two 8,000 gallon cisterns for irrigation use. Irrigation will not be required during several months of the year, so the irrigation season will start with full tanks. There is a backup system that uses potable water if the cisterns are empty. Our Design Case calculation shows that the irrigation water needed in July exceeds the 16,000 gallons that can be stored in the cisterns, pursuant to the required methodology and calculations. We calculate that we need 26,370 gallons of water based on mostly native vegetation with a small amount of sodded lawn (university requirement). The calculations and methodology presented in WEc1.2. assumes that all of the rainfall occurs at one time, fills the cisterns to their 16,000 gallon capacity and the rest bypasses to the municipal stormwater system. Is it possible to break the rainfall amount for July into four separate, smaller rainfall events that would occur throughout the month? (This is closer to naturally occurring events than one large monthly storm event.) By distributing the rainfall throughout July, the water in the cisterns would be used and replenished throughout the month. Any clarification you can provide on this issue is appreciated." "The rainfall amount calculated in four separate smaller rainfall events over the month of July would equal the total monthly rainfall (per records). The water stored at the beginning of the month plus the rainfall that can be collected and stored minus the planting requirement for a given month must remain positive throughout the year or an alternate water supply, potable water in this case, may become necessary. To achieve WEc1.2, the project must demonstrate that no potable water is necessary throughout the year. Calculate the supply and demand balance for every month of the year to demonstrate the rainfall/storage/demand interplay over a typical annual hydrologic cycle. Applicable Internationally." "None" "None" "X" "LEED Interpretation" "1602" "2006-10-17" "New Construction, Core and Shell, Schools - New Construction" "Background: Our project is a 40,000 sf, four-story office building on a tight urban site. Our goal is to capture and reuse as much rainwater as possible, for reuse as both irrigation water and sewage conveyance, and to apply this system to credits WE 1.2 and WE 2. Proposed Rainwater Use Strategy: We are proposing an annual water balance approach, similar in concept to the monthly water balance approach outlined in the CIR ruling for WE 1.2 and WE 2 dated 3/6/06. Per this ruling, it appears acceptable that water used for irrigation not be drop-for-drop from rainwater when served by the rainwater cistern, thereby allowing for greater rainwater usage year round. In our case, the local climate is such that there is very little rainfall during the summer months, while peak rainfall occurs during the winter months. Demand for sewage conveyance will be daily and relatively constant throughout the year, while demand for irrigation water will peak over the summer months and diminish during the winter months. The continuous draw from the rainwater cistern for sewage conveyance will result in optimal rainwater reuse, but rainwater will not actually be \'stored\' for dry season irrigation. We would like to request that a water balance over the course of a year, rather than monthly per the 3/6/06 CIR, be considered when determining the amount of rainwater saved and reused onsite. This will allow for greater water conservation for this project overall, while requiring a smaller, simpler rainwater collection system which will also save resources. Proposed System: Our rainwater system collects and reuses 39% of the annual rainfall that collects on the building roof. A cistern with a capacity of 5,600 gallons will collect enough rainwater over the course of a year to offset potable water use for 100% of irrigation needs and contribute to 71% of sewage conveyance needs. This equates to approximately 95,899 gallons per year of reused rainwater. This is much more than the amounts required by the credits to achieve 100% irrigation (8,080 gallons) and the amount of rainwater needed to achieve 50% sewage conveyance (20,000 gallons). In effect, with our proposed strategy we are saving and reusing an additional 67,819 gallons of water per year. A monthly water balance demonstrates that the cistern will provide enough rainwater for irrigation and toilet flushing for most months, but that there will be a few where it would fall short, due to the dry summer season. However this shortfall would be more than made up in the months on either side of the dry period. If we sized the cistern to store enough rainwater to irrigate through the dry season, the cistern would need to nearly double in size, and toilet flushing would need to switch over to city domestic supply during part of this period to reserve the cistern water for irrigation needs. Not only does this require more controls and piping, but it also requires a much larger tank. We believe that the building is best served by the smaller, simpler system that saves much more water per year, and conserves materials and resources. Request: Please confirm that an annual water balance on the collected rainwater and potable water savings is an acceptable approach for achieving credits WE1.2 and WE2. We have used an annual balance sheet, with daily rainfall inputs and daily irrigation and toilet use extractions, similar to that appearing in tables 4-2 and 4-3 of the Texas Guide to Rainwater Harvesting, to demonstrate that cistern sizing is appropriate to meet the overall rainwater savings per these credits." "The project is requesting approval for achieving WEc1.2 by demonstrating that the total annual on-site rainwater collection exceeds the total annual irrigation consumption. The project rainwater collection and storage system serves both toilet flushing and irrigation needs and is sized to meet a consistent baseline use throughout the year. The system does not, however, store enough water to meet peak summer irrigation demand. The proposed system design is not an acceptable alternative to achieving zero use of potable water for irrigation. The project design is making a trade-off between reserving captured water for irrigation and using it for the building plumbing. You can receive credit for the water reused for toilet flushing in WEc3. The monthly water balance referenced in the 3/6/06 CIR is the appropriate means for calculating water storage needs to achieve this credit. Applicable Internationally." "None" "None" "X" "LEED Interpretation" "1551" "2006-10-10" "New Construction, Existing Buildings, Commercial Interiors, Core and Shell, Schools - New Construction" "We are seeking clarification on the use of municipally provided non-potable water for achieving WEc3 under the LEED NC version 2.2 rating system. Use of municipally supplied non-potable water meets the intent of limiting or eliminating the use of potable water and reduces the burden on municipal water supplies. However, currently, the Reference Guide does not give clear direction with concern to WEc1, WEc2 & WEc3 and municipally supplied water: WEc1 states that water savings can be claimed through the use of ""water treated and conveyed by a public agency specifically for non-potable uses."" WEc2 states that water savings can be claimed through the use of ""municipally treated wastewater."" WEc3, however, makes no statements as to whether municipally supplied recycled water can count towards water saving calculations. However, the synergies between WEc2 and WEc3 calculations leads one to conclude that municipally supplied wastewater can be used for both credit calculations. Our project will be using municipally supplied non-potable reclaimed water for both irrigation and sewage conveyance (toilet flushing). Can you please clarify whether municipally supplied reclaimed water can be used to achieve both WEc3.1 and WEc3.2?" "Municipally reclaimed water is not applicable to WEc3 achievement. This credit focuses on fixture efficiency and on-site water reuse. Applicable Internationally." "10211, 10212, li-10284, 10284" "None" "X" "LEED Interpretation" "1576" "2006-10-02" "New Construction, Core and Shell, Schools - New Construction" "Credit Interpretation Request - Use of Reclaimed Water To minimize the amount of potable water use within the facility, Building 510 facility has been designed to utilize reclaimed water provided by West Basin MWD and the City of Torrance to serve all of the project\'s flushing waste water and irrigation needs. West Basin MWD have advised Honda that Reclaimed Water should be available to the site in time for the building being completed in May 2007. American Honda is working closely with West Basin MWD and the City of Torrance to expedite this process and ensure that the Reclaimed Water connection is made in line with this schedule. The facility is currently under construction and the plumbing scheme is approved and being installed to include the use of reclaimed water, and both West Basin MWD and the City of Torrance are fully involved in this process. Despite American Honda\'s obvious commitment to using Reclaimed Water, there are a number of City logistical issues that may delay the actual Reclaimed Water activation date beyond the proposed occupation of the building. These primarily relate to achieving the following City of Torrance approvals: 1.The civil engineering works required to make the final branch connection from the reclaimed water main to the site. This would involve civil work on what is a major street and the City is concerned about the traffic impact, which may drive the schedule for this work. 2.The City of Torrance Plumbing and Reclaimed Water Inspectors have the final say as to when the Reclaimed Water supply. To minimize the risk associated with these approvals, both of which are outside of American Honda\'s direct control, American Honda are ensuring that both West Basin MWD and the City of Torrance have been fully involved in both the design and installation of the reclaimed water system. To support this CIR, we have additional documents from American Honda, West Basin MWD and The City of Torrance, confirming their commitment to providing the reclaimed water supply to the building, which can be provided if necessary. Can you please confirm that it is acceptable to take credit for the use of Reclaimed Water within our LEED NC 2.1 submittal even though final activation may occur after the building\'s initial occupation." "To meet the intent of this credit provide a contract signed by both parties, indicating that this water will be provided within a one year period from the LEED submittal. Submittal documents must also indicate required infrastructure for the use of this water and state that the local jurisdiction has approved the use of the volume of water for this project." "None" "None" "LEED Interpretation" "1578" "2006-09-19" "New Construction, Existing Buildings, Core and Shell" "I am the LEED administrator for a Water Treatment Plant project (currently registered on LEED On-line, v2.2) We are not pursing LEED certification for the entire treatment facility. We are only pursuing LEED Certification for the primary building on the site (Administration/Operations Center). We have established a reasonable and consistent boundary for the subject building (including Sustainable Site considerations). As a water treatment facility, the project involves accessing water rights from the adjacent river for processing, treatment, and distribution of water to the public. In order to meet the criteria for WE Credit 1.1, 1.2 - Water Efficient Landscaping - we are considering: 1. Plant species factor 2. Use of captured rainwater - when available from the proposed on site stormwater retention basin and 3. Use of raw water - directly from the river For item 3 above, I have noted previous CIR\'s on this subject which deny the use of river water for this credit. I have also noted in the Reference Guide that the intent is to limit or eliminate the use of natural surface or subsurface resources for irrigation purposes. Yet, in the Reference Guide, page 115, under Requirements, ""Use of water treated and conveyed by a public agency specifically for non-potable uses"" is noted as a consideration. Most water (potable or non-potable) conveyed by a public agency is ultimately sourced from surface or subsurface resources. Therefore, it seems that an office building project, for example, could use non-potable water conveyed by our agency and that project would be eligible to gain the LEED credit. Whereas if our agency uses the same water for itself, the credit would not be granted. This raw, un-treated water, which would normally be processed through the treatment plant, will be diverted from the processing and treatment stream (saving energy and use of chemicals) and will be used directly for irrigation for the landscaping within the proposed LEED boundary surrounding the subject building on the water treatment plant site. We would like to confirm that USGBC concurs with our interpretation that this proposed source for irrigation water from the river (non-potable, raw water) will meet the intent of WE c1.1, 1.2. We believe that in essence, this raw water is equivalent to (is actually environmentally better than) ""Use of water TREATED and conveyed by a public agency specifically for non-potable uses"" as indicated on page 115 of v2.2 Reference Guide)." "Plant species factor and onsite captured rainwater are qualifying strategies to achieve this credit. Based on v2.1 WEc1.2 CIR rulings dated 1/20/04 and 11/5/2005, the use of surface water or water drawn from receiving waters is not an acceptable way to meet the credit intent. LEED-NC v2.2 WEc1 allows the, ""Use of water treated and conveyed by a public agency specifically for non-potable uses,"" however, these sources are not typically ""sourced from surface or subsurface resources."" Common sources include effluent from treatment plants and recycled graywater harvested from within the region. If this water treatment plant supplies water to offsite customers specifically for non-potable uses AND the raw water proposed for irrigation would otherwise be processed for this non-potable system, then the intent of the credit has been met. While the avoided energy and chemical inputs for this raw water are laudable, this is not a deciding factor. Applicable Internationally." "100000755" "None" "X" "LEED Interpretation" "5021" "2006-09-14" "New Construction" "Our project is community services foundation for homeless and disadvantaged persons providing a wide variety of community support services. As such we have identified four unique and separate user groups who will use this facility: Group 1:Clinic & Learning Center (visitors); Group 2: daily dining room (guests & volunteers); Group 3: 5 day per week staff and Group 4: 7 day per week staff. Each group has significantly different annual work days in the facility and therefore noticeably different water usages per fixtures. However, the LEED Online v2.1 WE Credit 3 Letter Template does not allow more than one Annual Work Days number to be considered when calculating the base and design case water use calculations. Alternative methods for calculating water usage have been submitted through prior CIRs and accepted by the USGBC for unique project situation but none of the alternative methods proposed seem to fit our project\'s specific circumstances. Therefore, we propose the following alternative method that accounts for each user group\'s annual work days and fixture uses by normalizing each group\'s male and female head count to one Annual Work Days count of 365 days per year. Examples: Group 1 works 260 day per yr or 260/365 = 71.23% of work days Group 2 works 365 days per yr or 365/365 = 100% of work days Group 3 works 250 days per yr or 250/365 = 68.49% of work days Group 4 works 351 days per yr or 351/365 = 96.16% of work days Using each of the above listed percentages, we then multiply each normalized percentage of work days per group by the total number of daily uses for both men and women by bathroom fixture. e.g.: If Group 1 has 58men each using the toilet once a day, the normalized usage would be (58*.7123) = 42 *1usage/day = 42 uses per day. The same formula would be applied to each fixture type for each user group\'s men/women head counts. These \'prorated\' or normalized male/female fixture uses allow for accurate, baseline and design case calculations using one normalized Annual Work Days of 365 days. This will enable us to correctly tabulate water use reductions using the established LEED-Online template. . Please confirm this method is acceptable for use on WE Credit 3 and clarify what supporting documentation should be submitted with the Credit Template. If this method is not acceptable please provide an alternative method for calculating this credit with more than user group total annual work days." "The project is proposing to derive a representative estimate of annual water usage for each user type by normalizing the fixture usage according to number of work days. The approach, as described, is acceptable for developing a combined estimate for diverse occupant types. This approach will essentially generate a composite # uses per fixture based on the four different user groups using the building. To support this approach in your submittal, you should provide the complete calculations used to develop the composite uses per fixture. Also, you should be sure to use a 50/50 male/female ratio unless there is strong evidence of an alternate ratio for the projected life of the building. Applicable Internationally. " "None" "None" "X" "LEED Interpretation" "1450" "2006-03-06" "New Construction, Core and Shell, Schools - New Construction" "Our project is a 104,000 sq. ft, three-story medical office building. We have designed a rainwater harvesting system with cistern capacity of 15,000 gallons to provide 100% of irrigation needs, an approximate reduction of potable water use for sewage conveyance of nearly 60%, and an overall 40%+ potable water use reduction on an annual basis by collecting 82% of the stormwater that falls on the site . Our question relates to the system control. We could program the controls to call on collected rainwater from the cistern for only irrigation during the summer months. All toilets during the summer months would thus be served by potable water only. We will begin the irrigation season with a quantity of water in the storage tank equivalent to the peak demand that occurs in July, and we can show that rainfall that will be collected during July is greater than the irrigation demand for that same month. While this strategy would ensure that, drop for drop, only rainwater is being used for irrigation, it does not maximize annual potable water savings. The scenario that ensures maximum potable water savings is to always use cistern water when it is available, and to use municipal water as a back up when the cistern can no longer provide collected rainwater. Our objectives are to minimize environmental impact, reduce potable water use at the project overall, and qualify for all of the credits in the ""Water Efficiency"" category. We would like confirmation that we can earn WEc1.1 and WEc1.2 by demonstrating that the system\'s capacity meets all of the required thresholds on an average monthly and annual basis, ensuring maximum potable water savings. Please note that once the plantings have been established, irrigation demand will decrease, further reducing the opportunity for potable water savings reductions under the controls scenario." "WE credit 1.2 may be achieved with the submittal of calculations demonstrating a site-wide water balance. The 2005 edition of the Texas Guide to Rainwater Harvesting offers a practical water model that can be used to demonstrate that, with storage capacity of 15,000 gallons, sufficient rainwater will be available to meet landscape irrigation and to offset 50% of potable water used for toilet flushing. The Guide is available online at http://www.twdb.state.tx.us/publications/reports/RainwaterHarvestingManual_3rdedition.pdf. The water quality from the collected water must conform to the minimum quality needs of the toilets. Applicable Internationally. " "None" "None" "X" "LEED Interpretation" "1296" "2005-11-05" "New Construction" "The intent of Water Efficiency Credit 1.2 is ""to limit or eliminate the use of potable water for landscape irrigation.""\n\nColorado has some of the most stringent water rights laws in the country. The site of our project, the University of Colorado, Boulder Campus draws 100% of its landscape irrigation water from Anderson Ditch, a ditch which is fed by rain and snow melt and Boulder Creek, which is primarily used for agricultural purposes. Our project, the Wolf Law Building, on the University of Colorado, Boulder Campus will be landscaped with xeric plantings; irrigated with high efficiency hardware informed by two weather stations; and irrigated entirely with Anderson Ditch (non-potable) water, which the University owns water rights to. Our question is: Does the USGBC agree that use of water from the Anderson Ditch qualifies to ""limit or eliminate the use of potable water for landscape irrigation""?\n\nAccording to the nationally renowned Water Rights Lawyers who will be occupying the building, the short answer is: Yes, Anderson Ditch is a non-potable water source according to State of Colorado Law. In addition, we have concluded that Anderson Ditch is a non-potable water source according the USGBC\'s stated definitions.\n\n""X According to the USGBC, ""potable water is water that is suitable for drinking and is supplied from wells or municipal water systems."" (LEED Reference Guide, page 89). Anderson ditch water is not suitable for drinking nor is it supplied from a well or a municipal water system. It is also stated on page 98 of the LEED Reference Guide, ""potable water is defined as water that meets drinking water quality standards and is approved for human consumption by the state or local authorities."" Anderson Ditch water does not meet drinking water quality standards.\n\n""X Per the WE credit 1.2 CIR (1/20/2004), ""The term \'potable water\' is used by the USGBC to differentiate \'recycled graywater\' (lavatory or shower water) and \'harvested rainwater\' from \'receiving waters\' (rivers, lakes, aquifers)."" Although the Anderson Ditch does not fall clearly into any of these three categories, it is not a river, lake, or aquifer. It is also stated in this CIR that "" \'industrial water\' delivered by the municipality, which is not treated, is nonetheless drawn from a source (Tennessee River) that provides the municipality access to water that is treatable and ultimately potable,"" therefore using any municipally supplied water would not satisfy the credit requirements. (Id.) Anderson Ditch is not municipally supplied.\n\nIn Colorado, most water is reused several times before it leaves the State, so river water, rainwater, and graywater, are equally ""treatable and ultimately potable."" Harvesting rainwater in Colorado is the legal equivalent of diverting water from a natural body of water. Under Colorado\'s prior appropriation doctrine, harvested rainwater cannot be put to a beneficial use (such as irrigation) without a plan for augmentation that replaces the depletions associated with that diversion. Furthermore, the use of graywater in Colorado requires treatment by an individual sewage disposal system and requires CDPHE permitting and monitoring.\n\nIn conclusion, we believe that the use of 100% Anderson Ditch Water for our project\'s (extremely water efficient) irrigation satisfies the intent of WEc1.2 and should earn LEED credit. Please verify." "The credit requirements specifically state ""captured rain or recycled site water"" as water sources applicable to this credit. Its intent, as noted in CIR ruling 9/19/05, is to promote the use of site-sourced reclaimed water for irrigation (if irrigation is needed) to achieve site self-sufficiency and reduce the demand for water that would otherwise be used elsewhere.\n\nIn Colorado, water supply for most irrigation ditches is taken from a watershed, river, or lake, diverted into a canal or ditch and delivered to downstream users as irrigation water or supplemental irrigation water. In most cases, if that water is not diverted into the irrigation ditch, it can be used for some other purpose, including potable water. Typically, a share of the ditch company entitles the shareholder to delivery of some amount of water for irrigation purposes. However, that share of the ditch can be sold to the City or a water district which will enable them to divert the share entitlement to the City or District potable water treatment plant. Typically, a developer or someone needing a source of potable water, will buy shares in the ditch, turn those shares over to the City or District and receive credit for potable water taps. If these conditions apply to the Anderson Ditch, its water could be considered potable and therefore could not contribute to the achievement of this credit.\n\nWE TAG has proposed a modification to this credit for LEED-NC version 2.2 that will allow renovated wastewater provided by a municipal agency to be used for WE Credit 1. For v2.1, the water from the ditch can be applied towards achieving WE Credit 2 and a related innovation credit. Applicable Internationally. " "None" "None" "X" "LEED Interpretation" "1327" "2005-11-03" "New Construction" "Can projects that do not include landscaping, such as in a zero-lot-line condition, meet the intent of WE Credit 1, ""Limit or eliminate the use of potable water for landscape irrigation,"" by not providing an irrigation system since no plants are included in the project scope?" "*NOTE: This ruling has been overturned by LEED-CI SSc1 CIR ruling, dated 4/20/2007* Yes, projects that do not have landscaping may earn two points under WE Credits 1.1 and 1.2 since potable water is not being used for site irrigation. As the credit is about performance and not action taken by the project team, the intent of the credit in this situation is met. Applicable Internationally. " "None" "None" "X" "LEED Interpretation" "5766" "2005-09-19" "New Construction" "Our project wishes to achieve WE credit 1.2 with the use of a temporary landscape irrigation system. Flexible HDPE piping (installed above ground), will be used to connect to the water meter and the code required back-flow prevention valve. All irrigation outlets will be drip type emitters and the system will be removed after the 2-year plant establishment period, wherein it will be relocated at the next building site for the same purpose. Will the use of HDPE pipe comply with the LEED requirements for the temporary irrigation system? " "The above-ground drip irrigation system described appears to be simple to install and remove and is acceptable as a temporary irrigation system for this credit. At the time of submittal, please provide cut sheets and a letter from the owner verifying that the system is above ground, how it can be easily removed, and will be terminated after the 2-year plant establishment period. Applicable internationally." "None" "None" "X" "LEED Interpretation" "5843" "2005-09-19" "New Construction" "The credit ruling dated 1/20/04 states that using any form of municipal supplied water for irrigation would not meet the intent of this credit. Is the issue that the water originates offsite, that it is supplied by a municipality, or that it is considered treatable and therefore ultimately potable? Our project is a new city building, and we have planned to use the city\'s reclaimed water supply for irrigation. Although the water does not originate on-site, it is ""recycled graywater"" from other sources. The city collects wastewater from homes and businesses, filters it, and then distributes this water for irrigation and toilet flushing instead of having to use surface or aquifer water. This approach can be more practical then individual graywater systems at each building, since many building owners cannot afford and would have difficulties maintaining their own graywater system, and the city graywater achieves the same water efficiency results as individual graywater systems. The municipality is supplying the water, but the municipality is also the Owner of the LEED project. We would like to know if using municipal supplied reclaimed water meets the requirements of this credit for this project. We\'d like to add as a footnote that we have been awarded this credit on a previous project using this same strategy." "Neither municipally supplied water or any other water treated off site is accepted under this credit as it is currently written. As noted in CIR ruling dated 11/5/04, the credit\'s intent is to promote the use of site-sourced reclaimed water for irrigation (if irrigation is needed) to achieve site self-sufficiency and reduce the demand for water that would otherwise be used elsewhere. The credit requirements specifically state ""captured rain or recycled site water,"" thus disqualify water treated off site. CIR ruling dated 1/20/04 stated that ""using any form of municipal supplied water for irrigation would not meet the intent of this credit."" This issue has previously been brought to the attention of the LEED Water Efficiency Technical Advisory Group which confirmed that municipally supplied graywater cannot contribute to achievement of this credit in the context of version 2.1. However, the WE TAG has proposed a modification to this credit for Version 2.2 that would allow renovated wastewater provided by a municipal agency to be used for WE Credit 1. This modified language is currently undergoing public review prior to balloting. Under Version 2.1, consider using your proposed non-potable water source for achieving WE Credit 2 and an innovation point for doubling that credit\'s requirement. Applicable internationally." "None" "None" "X" "LEED Interpretation" "5824" "2005-08-16" "New Construction" "The 12/21/04 Ruling to our WEc1.1 CIR stated the following: ""if the project\'s certification submittal demonstrates that the quantity of anticipated rainfall flowing from the site to the Potomac River is equal to 50% of the site\'s irrigation needs, WE Credit 1.1 will be awarded. This is because the net effect of drawing that amount of water from the lagoon is the same as if the rainwater was captured on site."" Later, a 4/4/05 Ruling to a WEc1.2 CIR stated: ""The approach of designing rainwater storage for a ""normal"" rainfall year and providing potable water as backup is acceptable as implied by the LEED-NC Reference Guide calculations section."" We have two questions based on these Rulings. 1) We have performed calculations that demonstrate that the quantity of anticipated rainfall flowing from the site to the Potomac River is equal to over 100% of the site\'s irrigation needs. Please confirm that we can earn WEc1.2 as well based on extrapolating the 12/21/04 WEc1.1 Ruling. 2) The Government is considering the possible need for a potable water back-up to the lagoon-fed system described in our 12/3/04 WEc1.1 CIR for use in drought conditions. Please confirm that, combined with our lagoon-based compliance path, the provision of a back-up potable water supply will not compromise our ability to earn WEc1.2." "Based on the description of your project, credit WEc1.2 may be achieved with the submittal of calculations demonstrating that the quantity of ""normal"" anticipated rainfall meets 100% of your irrigation needs per CIR ruling 12/21/2004. As stated in CIR ruling 4/4/2005, providing potable water as a backup is acceptable as implied by the LEED-NC Reference Guide calculations section." "None" "None" "LEED Interpretation" "1166" "2005-07-19" "New Construction" "The LEED Letter Template and calculation equations for this credit allows for the reduction of potable water use by subtracting annual graywater or rainwater harvest. Our building project will include the design of a testing lab that requires the maintenance of a constant fully saturated environment (100% humidity) achieved through a water misting system. The system will be continuously supplied from the potable water supply and excess water will discharge to the sanitary waste drain. In order to reduce the waste of this potable water supply the misting system will include a provision where the excess potable water will be collected and re-circulated rather than made up with potable water. This reclaimed potable water will represent a significant potable water savings versus the baseline approach of draining it to sanitary waste.\n\nWe, therefore, request an interpretation as to whether the reclaim of the excess potable water to be used for this process may be counted as graywater harvest for successfully meeting the intent of Water Efficiency Credit 3.2." "The water used by the water misting system would be classified as process water. WEc3 is specifically focused on the water usage of plumbing fixtures covered by the Energy Policy Act of 1992 (EPAct). These include toilets, urinals, lavatory faucets, kitchen faucets and metering faucets. Per CIR ruling dated 3/9/2004, process water includes, but is not limited to, water use from cooling towers, dishwashers and clothes washers. Optimization of process water use is eligible for LEED credit under the Innovation in Design category. Please see IDc1.1 CIR ruling dated 8/31/2004 for guidance on attempting this as an innovation credit. Applicable Internationally. " "730, 808, 2465, 5044, 5291, 100000916" "None" "X" "LEED Interpretation" "6039" "2005-07-06" "New Construction" "We believe that our project has gone a step better than drip-irrigation, and therefore deserves credit WE1.1. Project: 270,000 sf corporate campus Project Area: 130.5 acres (approx. 85% of which will remain as open, undisturbed space.) Total Planted Area: 13.2 acres Planted Area w/ Irrigation: 1.75 acre turfgrass ballfield (located on an area, currently being used for construction staging, which was cleared by a previous owner.) Planted Area w/ No Permanent Irrigation: 11.45 acres of native species mixed planting (purpose is to revegetate the areas disturbed by construction, augment areas of sparse existing vegetation, and control erosion.) We believe this project landscaping has achieved exceptional water efficiency in two ways. First: manicured landscapes seem to be preferred in our area. In contrast to nearby projects, very little, if any, natural vegetation will be removed for relandscaping. In addition, the project team took unusually extensive measures to preserve the natural vegetation and therefore minimize the need for irrigation. As a result, only 10% of our site will be planted and only 1.3% will be irrigated, which we believe is unusual and significant in terms of water savings. Second: during the design process, we considered several different irrigation options. Without changing the planted area, we considered the following scenarios using the LEED WE1.1 calculations. A. Baseline case uses sprinklers for entire planting area (with average species): requiring approx. 2.2 million gallons. B. Design case uses drip irrigation for mixed planting area (with average species): requiring approx. 1.5 million gallons. (78% of which is for the drip irrigation system) C. Final design case goes a step further, in the spirit of credit WE 1.2) and eliminates the need for permanent irrigation in the mixed planting area (the majority of irrigation): requiring approx. 0.33 million gallons. The final design case saves 1.87 million gallons, a 67% reduction over the original baseline case. " "Using irrigation for only a small portion of the 13.2 acre planted area and native landscaping for the remainder meets the intent of the credit. The statement about comparison to adjacent landscapes is not basis for credit achievement. However, the project appears to comply with the credit requirements for the planted area. Note that data for existing vegetation will be the same in both the baseline and design cases (if it is not replaced). Drip irrigation is suggested as one possible strategy for reducing irrigation demands, but it is not a requirement for the credit. When calculating your water savings, you can compare the baseline to the final design case without considering an intermediate case using drip irrigation. Consider possibility of achieving SS Credit 5.1 and/or 5.2. Applicable internatioanlly." "None" "None" "LEED Interpretation" "998" "2005-04-04" "New Construction" "We wish to meet the intent of WEc1.2 by irrigating entirely with non-potable water. To do this, we will provide on site storage for rainwater and/or groundwater from the basement de-watering system. The storage will be sized to provide irrigation for the project in all normal years. However, in drought years, if the tank does not fill up with enough water to meet our irrigation requirements, we would like to have a backup system that relies on potable water. Note that if groundwater is used (and we may rely entirely on rainwater storage, depending on the outcome of our study of groundwater volume to be conducted this summer during the dry months), it will not be ""potable"" as it could not be used for drinking without a well permit which is difficult to obtain and will not be sought for this project.\n\nWe propose to document the plant types, the irrigated area, and the typical rainfall (or groundwater volume) for a ""normal year,"" along with the catchment area and the storage tank size, to show that we have designed a system that can provide for all our irrigation needs in a normal rainfall year. Please confirm that this strategy meets the intent of WEc1.2, even if it is connected to a potable water system for backup in drought years." "Capturing rainwater for irrigation purposes is a commendable approach to eliminating potable water use. Likewise, according to the WE c1.2 7/10/2003 CIR ruling, irrigating with water diverted from a basement de-watering system is acceptable, but should be explained in a credit narrative. Thus, the described approach meets the intent of WEc1.2\n The approach of designing rainwater storage for a ""normal"" rainfall year and providing potable water as backup is acceptable as implied by the LEED-NC Reference Guide calculations section. Alternatively, the most effective approach to achieving this credit is to landscape with drought-tolerant plant species. This strategy could potentially eliminate the need for potable water backup during extended dry periods.\n\n **Update October 1, 2013: This ruling has been made applicable to WEc1 in LEED v2009." "557" "None" "X" "LEED Interpretation" "5887" "2004-12-21" "New Construction" "The Pentagon lies immediately adjacent to a lagoon off of and fed by the Potomac River, which is itself ""receiving"" water body containing non-potable water, all of which is also inherently fed by rainwater. Previous Credit Rulings have stated that water drawn from a source (such as a river) ""that provides the municipality access to water that is treatable and ultimately potable"". Our desired irrigation strategy would involve pumping water directly from the lagoon off of the Potomac River, a lagoon which is currently providing some of the irrigation water used elsewhere on the Pentagon site and which is also currently used for cooling central plant equipment. We do not intend any interim treatment of this water other than on-site filtration for large contaminants, and do not intend any additional ""catch basin"". We feel that the very direct access that the facility has to the water source from the lagoon, which is itself is something of a large-scale catch basin, should be considered equivalent to providing an intermediate catchment source that would overflow into and be supplemented by the receiving waters themselves, as proposed by the project Inquiry dated 6/28/04. In terms of the net environmental benefit, we do not see any functional difference between the previously proposed strategy and our proposed strategy, and believe that this water should at least allow us to earn Water Credit 1.1 as long as back-up water used in addition to the lagoon water amounted to a minimum of 50% total non-potable water, and possibly Water Credit 1.1 as long as back-up water used in addition to the lagoon water amounted to 100% non-potable water." "The man-made lagoon you describe does not appear to be completely equivalent to the rainwater catchment basin described in the 6/28/04 CIR. From your description, there is no segregation of your site rainwater and the Potomac River water. Per the 1/20/04 Ruling under WEc1.2, irrigation water drawn from a receiving water does not qualify as nonpotable water under this credit. However, if the project’s certification submittal demonstrates that the quantity of anticipated rainfall flowing from the site to the Potomac River is equal to 50% of the site’s irrigation needs, WE Credit 1.1 will be awarded. This is because the net effect of drawing that amount of water from the lagoon is the same as if the rainwater was captured on site." "None" "None" "LEED Interpretation" "5962" "2004-11-05" "New Construction" "This project includes landscaped area that will be served in its entirety with a permanent irrigation system connected to a dedicated reclaimed water distribution system. This reclaimed water comes from the local wastewater treatment plant and is blended secondary and tertiary treated water. Plants specified include mostly native species and drought resistant species that require minimal supplemental watering after an establishment period. Approximately 3% of the trees and palms are Magnolia trees and Citrus that are not native to the location. To serve these trees during the establishment period, a 1 in. potable irrigation line will be provided in two narrow courtyards with hose connections along one side of the hardscape in each courtyard for hand watering. These courtyards are also served with a permanent irrigation system connected to the dedicated reclaimed water distribution system. A backflow prevention device will be added per city requirements. While it is understood that this line could be converted to provide irrigation with potable water in the future, the owner has stated that they will only water the magnolias and citrus until they naturalize after which time the trees will receive supplemental irrigation with reclaimed water. Will this irrigation approach prevent the project from receiving attaining WE credit 1.2?" "Your approach is not acceptable for either of the credit\'s compliance paths. 1) Water from a local wastewater treatment plant is not applicable to WE Credit 1.2. Intending to promote the use of site-sourced reclaimed water for irrigation (if at all needed), the credit requirements specifically state ""captured rain or recycled site water"" and thus disqualify water treated off site. Furthermore, the WEc1.2 ruling dated 1/20/04 stated that ""using any form of municipal supplied water for irrigation would not meet the intent of this credit."" Consider using your proposed non-potable water source for achieving WE Credit 2. 2) Hard piped underground irrigation lines are not acceptable as a temporary irrigation system during the landscaping establishment period. See WEc1.2 ruling dated 9/24/2003 for further explanation. The use of hose connections is an acceptable strategy (see WEc1.2 ruling dated 7/10/03 for precedent allowing hose bibs). " "None" "None" "LEED Interpretation" "5692" "2004-10-18" "New Construction" "Our LEED site contains multiple buildings for a nature center, which covers a large acreage of land. Our team decided to collect rainwater for irrigating landscaping adjacent to the orientation center via a permanent irrigation system. After completing initial calculations, we determined we couldn\'t collect enough rainwater to also irrigate the native landscaping buffer strip along the parking lot and entrance road, which is away from the orientation center buildings. Our current plan is to install a temporary irrigation system, fed by potable water, for this strip for an establishment period of 2 years. The remainder of the project\'s LEED site will not have any irrigation system as it is native vegetation. The two listed submittals for this credit (no potable water for irrigation and no permanent irrigation system) appear to be an either/or situation and each seems to apply to the entire ""project site."" We feel our methodology meets the intent of this credit, which is to ""limit or eliminate the use of potable water for landscape irrigation""; however, before we proceeded we wanted to receive feedback on the likely outcome of this strategy. As we have multiple buildings and areas that make up our LEED site, we are inquiring to see if we can use both submittal methods for different parts of our site in order to meet this credit\'s intent. As part of the corresponding committee for the LEED for Multiple Buildings, we consulted the draft LEED Campus Application Guide but found no Supplementary Campus Application Guidance related to this topic. If a ruling is made in favor of this proposal, we would appreciate seeing the Application Guide reflect this change as well as LEED-NC v2.2. Thank you. " "The project is proposing to install a rainwater collection system for irrigation use on a majority of the site. Since the amount of rainwater collected will not meet 100% of the site\'s irrigation needs, the project team has proposed to install native plants and a temporary irrigation system to be used only during the two-year establishment period for the area not served by the rainwater collection system. It is acceptable to combine the proposed credit strategies, whether across multi-building or single building sites, to meet the intent of the credit. The project team should submit appropriate documentation supporting the design of the rainwater collection system and demonstrating the extents of the supplemental temporary irrigation system. \n\nUpdate April 15, 2011: Please note that all 2009 projects in multiple building situations must follow the 2010 Application Guide for Multiple Buildings and On-Campus Building Projects, located here: https://www.usgbc.org/ShowFile.aspx?DocumentID=7987. 2009 project teams should check this document for up to date guidance on all multiple building issues. Applicable internationally." "None" "None" "X" "LEED Interpretation" "5723" "2004-10-18" "New Construction" "Our project is a 700,000 square foot health centre. Because of the varying occupant numbers in a hospital (including patients, staff and visitors) we propose an alternative method of calculating this credit. Rather than basing the calculations on the number of occupants, we have calculated our water use based on the total number of each type of applicable fixtures in the building and the estimated number of uses for each of these. For example, for the public W.C. our calculation is as follows: Total Daily Water Use (Public WC) = Total Number Of Fixtures x Estimated Daily Uses x Flow Rate(GPF) x Duration As required, our calculations use the same fixture count and daily use numbers for the base and proposed case. This should provide a reasonable representation of base and proposed case water use. As per previous rulings, our calculations include all flush fixtures and the following flow fixtures: - public and private lavatories - public and private showers - kitchen faucets - clinical, scrub up and service lavatories Also per previous rulings, we are excluding the following as process loads: - eyewash fountains, emergency showers, water coolers, and water fountains dishwashers etc. Please confirm that our approach is acceptable. " "Since a hospital project has a variable and transient occupancy, the project team has proposed an alternative method for calculating water use reduction based on estimated daily fixture uses rather than estimated occupant usage. The proposed method sets a usage baseline for each fixture type. The base case and design case calculations use this common usage factor to determine water use savings. While it is preferable for projects to use the prescribed occupant usage factors for calculations under this credit, it may be difficult to obtain a reasonable representation of water usage in projects with high transient occupancies. The proposed method is an acceptable alternative for use by projects of this type to calculate water use savings under this credit. " "None" "None" "LEED Interpretation" "829" "2004-08-27" "New Construction, Existing Buildings, Commercial Interiors, Core and Shell, Schools - New Construction" "Summary: Interpretation ruling pertaining to establishing the calculation baseline for Water Reduction Credits 3.1 & 3.2 when on-site tests have been conducted, and demonstrate that the supply water pressure levels (psi) to the fixtures are substantially below the 80 psi referenced within the Energy Policy Act of 1992. Context: The scope of the project incorporates new construction of four residential halls on a college campus, which house more than 250 students and staff. Three of the buildings are three stories, and the other is four stories. Description: The residence halls are incorporating a range of fixtures that are below the flow rates within the Energy Policy Act of 1992 (dual flush toilets, and faucets within the kitchens, kitchenettes, bathrooms & apartments). The showers in the residence hall are the largest water consumer (by a large %) within the residence hall buildings. To begin to understand the water amount actually used on the project, the owner conducted some initial on-site tests to determine the supply pressure to the plumbing fixtures, and how that translated into the actual flow. On-site tests for one of the buildings have been conducted on the flow rates of the shower heads with the following results: Fixture type currently installed = 2.5 gpm 1st floor: 52 psi static, 2.10 gpm 2nd floor: 46 psi static, 1.92 gpm 3rd floor: 41 psi static, 1.79 gpm 4th floor: 37 psi static, 1.85 gpm Question: o Would the design case account for the lower psi (reduced water use) by multiplying the \'Water Use\' column within the calculation template by the percentage of supply/baseline? For example for a shower on the first floor the \'Water Use"" would be multiplied by 65% (52/80) or by just including 2.10 gpm as the flow rate for the fixture on this floor? o What is the appropriate methodology for establishing the calculation baseline when the water pressure supply rate (psi) is substantially lower than the 80 psi outlined as the baseline flow rates under the Energy Policy Act of 1992?" "[Note: this ruling was revised on 9/1/04.] The underlying assumptions used for calculating projected water use savings should remain consistent between the baseline and design case. Supply water pressure varies across the United States and within individual buildings (as you note in your inquiry). Flow rates at 80 psi are used for the calculations in this credit for consistency and to reward use of efficient fixtures. It is recommended that all projects use the flow rates reported by the manufacturer at 80 psi for comparison with the Energy Policy Act of 1992 flow rates. If you wish to use on-site tests to report the most accurate volume of water use, you must be consistent throughout all fixtures and test both baseline and design fixtures. It is not acceptable to use flow rates at 80 psi for some fixtures and actual flow rates for other fixtures. Measurement can also be used to account for the benefits of whole-building strategies, e.g., flow restrictors at the water service entrance. Applicable Internationally. " "100001790, 100001791" "None" "X" "LEED Interpretation" "5834" "2004-07-19" "New Construction" "The City of Little Rock Code for Irrigation requires an irrigation system for developments of one acre or larger. The irrigation system will not be connected to the City of Little Rock potable water system. Rainwater will be collected from the roof into a catch basin. The catch basin will hold 8,000 gallons of captured rain water. The catch basin is connected to a marina which is part of the site. The marina is a dock and access off the Arkansas River through a lock gate. All excess water from the basin is diverted into the adjacent marina. Once the 8,000 gallons of water held in the catch basin is used for irrigation, water is pull from the adjacent marina. A pump and filter will be provided to pull water from the marina and continue through the irrigation system consisting of conventional spray heads and drip irrigation. The marina is maintained to a relatively constant level by mechanical means. Approximately 80% (44,000 sf) of the site landscape contains a native vegetation with minimal to no irrigation. The remaining 20% (11,000 sf) not native to the state has similar water use requirements. Does this design qualify for WE credit 1.2?" "As noted in CIR ruling 1/20/2004, water that is drawn from a source such as the Arkansas River is treatable and ultimately potable. However, if the project\'s certification submittal demonstrates that the quantity of water from anticipated rainfall and the 8,000 gallon capacity of the catch basin meets the needs of the 20% of the site that requires irrigation, the credit will be awarded." "None" "None" "LEED Interpretation" "808" "2004-07-08" "New Construction" "This project is a prison complex, comprised of multiple buildings with multiple uses. As such, a wide variety of plumbing fixtures are required to be installed, many of which are not expressly addressed within the Energy Policy Act of 1992. This inquiry relates to how certain unconventional fixtures should be addressed within the context of the WEc3 Letter Template Calculator. Fixture types installed at this facility that we believe fall within the purview of EPAct 1992, and should be included in our calculations, include: combination units in the cells, lavatory sinks, water closets, urinals, hand wash fountains, hand wash sinks, janitor sinks, kitchen sinks, and showers. We have included all such fixtures in our WEc3 calculations. Based on several rulings within WEc3.1 and WEc3.2 which specifically state that optimization of process water use is not eligible to receive credit under WEc2 and WEc3 and that process water includes, but is not limited to, water use from cooling towers, dishwashers and clothes washers, fixture types installed at this facility that we believe can be excluded from our calculations are: institutional clothes washers, institutional dishwashers, eyewash fountains, emergency showers, barber sinks, clinical sinks, bar sinks, plaster sinks, scrub sinks, maintenance sinks, permanent water coolers, and permanent water fountains. We would like confirmation that our understanding of the included and excluded fixtures is correct." "Your understanding is correct. The clothes washers, dishwashers, eyewash fountains, emergency showers, water coolers, and water fountains are exempt from the requirements of the Energy Policy Act of 1992 (EPAct). The faucets addressed by the EPAct only include lavatory faucets, kitchen faucets and metering faucets. The sinks mentioned above are not covered by the EPAct and can be excluded from the calculations. As stated in WEc2 CIR Ruling dated 3/9/04, optimization of process water use is eligible for LEED credit under the Innovation in Design category. Applicable Internationally. \n\n***Update 1/1/13: This LI is non-applicable to LEED rating systems other than LEED NCv2.0" "730, 1166, 2465, 5044, 5291, 100000916" "None" "X" "LEED Interpretation" "754" "2004-04-19" "New Construction" "We are designing an addition/renovation to a college campus building.\nThe occupancy count will remain the same pre-construction and post-construction.\nNot all of the existing fixtures will be replaced or upgraded for the addition/renovation.\nSome existing fixtures will be removed, some will be replaced and some fixtures will be added.\nA small percentage of baseline case fixtures will remain (20%).\n\nIn calculating the usage of baseline case and design case for a particular fixture, is it acceptable to calculate 20% of the occupants to use the baseline case fixtures and 80% to use the design case fixtures? " "For LEED calculations, the baseline case is defined as the building with fixtures that meet the Energy Policy Act requirements (see page 100 of the LEED v2.1 Reference Guide for EPACT fixture ratings), NOT the actual fixtures existing prior to retrofit. The design case is defined as the building with the actual fixtures installed. In the project cited, this would include the new fixtures installed AND the existing fixtures remaining.\n\nThe calculation methodology for this credit is described in detail in the LEED Reference Guide. The LEED v2.0 Calculator and the v2.1 Letter Template provides spreadsheets for creating the baseline and the design cases. The calculations are based on the building occupants\' usage of fixture types. For both the baseline and design cases, the occupants\' usage patterns need to be consistent, which includes the number of occupants, frequency and duration of use for male and female of a fixture type with the corresponding water volume consumed (in gallons per minute or gallons per flush).\n\nThe proposed methodology for occupant use of the new fixtures (80%) and the existing fixtures (20%) is acceptable, but only if entire restrooms have been retrofitted with new fixtures. If there has been a mix of new and existing fixtures within one or more restrooms, a different methodology must be developed by the project team and justified based on the use patterns of the individual restrooms. Applicable Internationally. " "None" "None" "X" "LEED Interpretation" "731" "2004-03-24" "New Construction" "Our project involves 7 buildings around a university quadrangle site. In order to reduce irrigation water consumption, our design strategy is to reduce the area of irrigation by only irrigating the turf grass areas that will be exposed to high foot traffic. In all other landscape areas, we are using low-maitenance native plants and providing no irrigation.\n\nOur calculations will show that total irrigation water consumption has been reduced by more than 50% versus a Baseline Scenario that irrigates all landscape areas on the site.\n\nWE 1.1 states that the goal of this credit is to reduce potable water used for landscape by 50%. But the criteria only lists two methods for achieving this goal - high efficiency irrigation technology or recycled rain/site water. Our design strategy achieves the 50% reduction goal by limiting the quantity of area irrigated. Is there any reason this strategy would not count for this LEED credit?" "The strategy you propose could be achieved by virtually any project simply by manipulating the area for irrigation and is not acceptable to earn this credit. This is especially true in a campus situation where LEED project boundaries are sometimes difficult to define. This credit was intended to encourage the use of high efficiency irrigation equipment or the use of non-potable water for irrigation purposes only. The calculation methodology for this credit is explained in the LEED v2.1 Reference Guide (May 2003) beginning on page 84. This methodology requires that planting types should correspond and landscape areas and other factors should not change between the design and baseline cases. In your situation the area of turfgrass which will not be irrigated should be excluded from the design and baseline calculations. Applicable Internationally. " "None" "None" "X" "LEED Interpretation" "5969" "2004-03-23" "New Construction" "This project is a visitor center for a state park. The state park includes the visitor center, picnic shelters, comfort stations (housing toilet facilities), trails, etc. The visitor center consists of a lobby, exhibit area, gift shop, auditorium, office space, conference room and break room. The building will be open 363 days/ year, between 8 AM and 4:30 PM. The building will have 3 full-time employees (2 male, 1 female). Projections for visitors are about 75,000 per year, which averages out to 207 per day. The Park Manager assumes that visitors will spend between 15 minutes and 2 hrs in the building, so we\'re estimating 1hr per visitor. It takes 8.5 visitors to create one Full Time Occupant. Thus the building would have an occupancy of 25 visitors plus 3 employees, totaling 28, 14 male, and 14 female. Taking the assumptions from the reference guide, we come to the following daily usage numbers: WC: 56 total uses, Lavatory: 84 uses, Urinal: 28 uses, Kitchen sink (for employee use only): 3 uses. Of these total uses, 9 lavatory and 9 WC and urinal uses combined are by the 3 full time employees. Thus, approximately 36% of the visitors will use the facilities (assuming one use per visitor). We assume some visitors will not use the facilities at all while in the park, while others may use those located in the comfort stations throughout the park instead of those located in the visitor center. Is this calculation for this building type acceptable for this credit?" "Yes, converting visitor numbers to Full Time Equivalent occupants and then applying the daily uses from the LEED Reference Guide is an acceptable approach for this project type. Be sure that the daily uses are the same for the design and baseline cases. " "None" "None" "LEED Interpretation" "5981" "2004-03-09" "New Construction" "This USGBC administrative CIR is in regards to process water loads. " "This USGBC administrative action serves to rescind the WEc2 ruling dated 6/28/02 and to clarify the casual mention of cooling towers and appliances on page 102 of the LEED-NC v2.1 Reference Guide. Only those fixtures regulated by the Energy Policy Act of 1992, the reference standard for WEc3, are to be included in WEc2 and WEc3. In accordance with precedent set by previous LEED-NC v2 certifications and in order to maintain consistency in the application of LEED-NC v2 across an increasingly broad range of building types, optimization of process water use is not eligible to receive credit under WEc2 and WEc3. Process water includes, but is not limited to, water use from cooling towers, dishwashers and clothes washers. Optimization of process water use is eligible for LEED credit under the Innovation in Design category. To date, no project has received credit towards LEED certification under WEc2 or WEc3 for optimization of process loads. Applicable internationally. " "None" "None" "X" "LEED Interpretation" "730" "2004-03-09" "New Construction" "This USGBC administrative CIR is in regards to process water loads." "This USGBC administrative action serves to rescind the WEc2 ruling dated 6/28/02 and to clarify the casual mention of cooling towers and appliances on page 102 of the LEED-NC v2.1 Reference Guide. Only those fixtures regulated by the Energy Policy Act of 1992, the reference standard for WEc3, are to be included in WEc2 and WEc3. In accordance with precedent set by previous LEED-NC v2 certifications and in order to maintain consistency in the application of LEED-NC v2 across an increasingly broad range of building types, optimization of process water use is not eligible to receive credit under WEc2 and WEc3. Process water includes, but is not limited to, water use from cooling towers, dishwashers and clothes washers. Optimization of process water use is eligible for LEED credit under the Innovation in Design category. To date, no project has received credit towards LEED certification under WEc2 or WEc3 for optimization of process loads. Applicable Internationally. " "808, 1166, 2465, 5044, 5291, 100000916" "None" "X" "LEED Interpretation" "690" "2004-01-20" "New Construction, Existing Buildings, Core and Shell, Schools - New Construction" "In lieu of potable domestic water, we are planning to tap into a municipal ""industrial water"" line for landscape irrigation use and retention pond supplement. The municipal water system originates from the Tennessee River, and is piped to the treatment plant. Most of the water is treated and distributed as potable water but a portion is released without treatment as ""industrial water"" for use in cooling systems and irrigation. Would this municipally supplied industrial water source meet the credit requirements for WE 1.2 for no potable water use in irrigation?\n\nIf this source is considered potable water - not meeting the credit intent - would using captured rainwater from an on-site retention pond meet the credit requirements (WE1.1 or 1.2) if, on occasion, water from the industrial water line was added to keep the pond full?" "USGBC ruled in WEc1.1CIR dated 1/13/03 that ""the intent of this credit is to encourage water efficient or xeriscape landscaping practices, which require little to no irrigation. If, after such practices are implemented, irrigation is still necessary to maintain the landscape, then the applicant project can follow two paths for credit compliance: 1) high efficiency irrigation technologies; or 2) the use of non-potable water for irrigation purposes. The term \'potable water\' is used in this credit to differentiate ""recycled graywater"" (lavatory or shower water) and ""harvested rainwater"" (cisterns or collection ponds) from water drawn from ""receiving waters"" (rivers, lakes, aquifers)."" Even though this \'industrial water\' is not treated, it is drawn from a source (Tennessee River) that provides the municipality access to water that is treatable and ultimately potable. Therefore, using any form of municipal supplied water for irrigation would not meet the intent of this credit. Applicable Internationally. " "None" "None" "X" "LEED Interpretation" "6026" "2003-11-03" "New Construction" "We are specifying flush valves which are compliant with EPact 92. They also have adjustment feature to reduce further than nominal compliance values. If we adjust to achieve 20% reduction, and owner finds the adjustment performs satisfactorily, will Credit 3.1 be granted?" "The flow rate from an adjustable flush value could be utilized in the LEED calculations for WE Credit 3.1. The flow rate setting should be explicitly specified (at 0.8 GPF in your example). Documentation from the product manufacturer should show that the flush valve is adjustable and to what range it is adjustable. In addition, verification of the installed, actual GPF should be provided by the installer and verified by the commissioning agent. The granting of WE Credit 3.1 will be determined by a review of the calculations and documentation provided during the certification process." "None" "None" "LEED Interpretation" "5929" "2003-10-06" "New Construction" "This CIR describes our methodology for developing baseline water use for PSU Broadway Housing, a residential project. Please advise if this methodology is acceptable. Our baseline water use estimates have been calibrated to data from a 1999 American Water Works Association (AWWA) study on residential end uses of water. The study lists per capita daily water usage rates for conventional and ""more efficient"" water fixtures. The conventional fixture values were used for all baseline fixtures, except toilets. For toilets, the water efficient fixture rate was chosen as it corresponds to 1.6 gallons/flush, the current code standard. The AWWA information can be accessed on the following website: http://www.awwa.org/Advocacy/pressroom/statswp5.cfm All fixtures used code or standard flow rates; the daily uses and/or durations were adjusted for calibration, such that the overall gallons/person/day for each fixture type matched the study values. Calibration of Baseline Water Use by Fixture Fixture Type -- AWWA LEED Baseline Kitchen sink -- 6.7 = 2560 gal/day/384 occ. Lavatories -- 4.4 = 1680 gal/day/384 occ. Faucets -- 11.1* Sum of above = 11.1** Toilet -- 9.6* 9.6 = 3686 gal/day/348 occ. Shower -- 12.6 12.5 = 4800 gal/day/384 occ. Clothes Washer -- 15.1 15.0 =5760 gal/day/384 occ. * Based on low-flow fixture rates (1.6 gal/flush) ** The AWWA study listed only the overall faucet usage; breakdown to usage by kitchen sink and lavatory was based on professional judgment. " "The LEED Reference Guide and the LEED calculators (found in v2.0 Calculator or v2.1 Letter Template) provide guidance on the calculation methodology that should be used for this credit. A list of all water-using fixtures and frequency-of-use data needs to be input into the spreadsheet. Frequency-of-use data includes the number of male and female daily uses, the duration of use and the water volume per use. The water use calculations are based on building occupants\' usage of fixtures that are necessary for the occupancy of the building, such as for drinking water and conveying sewage, and does not include process loads (e.g. dishwashers, clothes washers). For LEED calculations, the baseline case uses fixtures that meet the Energy Policy Act requirements (see page 100 of the LEED v2.1 Reference Guide for EPAct fixture ratings). The design case would then account for water efficient fixtures that meet or exceed the Energy Policy Act requirements. Calculations also include water-source strategies such as rainwater and graywater use. The 1999 American Water Works Association (AWWA) study on residential end uses of water does not provide information on whether the baseline calculations are based on fixtures that meet the Energy Policy Act of 1992, and should therefore not be used for LEED calculations. As there are no set criteria for determining daily use or duration of use, the project can estimate both of these items based on the project and occupants or refer to this study as a guide in determining the frequency-of-use data. " "None" "None" "LEED Interpretation" "5697" "2003-09-24" "New Construction" "Our plant materials selection contains mostly native species and those that are not are drought resistant species that require no supplemental watering after the establishment period of two years. During the establishment period a standard irrigation system will be installed in all shrub areas and 8.4% of lawn area as is required by the City of Beaverton until plant materials are established. Considering the cost of labor, water conservation and human error factor in water management monitoring in providing watering with a temporary/portable system, the system selected is a timed underground system with pop up spray heads, which is intended to be used only until establishment of plant materials, at the end of which establishment period the system will be disconnected. Both a drip system and a temporary/portable system were considered for use but rejected because of the vulnerability of these systems to vandalism in a school environment. We believe that the system we have selected for temporary establishment support is the more cost effective system and when the system is disconnected and abandoned in place, it will have achieved the intent of WE Credit 1.2 by providing an indigenous drought resistant landscape that will use no potable water for irrigation from that point on. Will the use of this irrigation system prevent us from receiving WE credit 1.1. and WE credit 1.2? " "The temporary pop-up strategy you describe here is not an acceptable one to meet WEc1 for a number of reasons, but primarily because there is no way to ensure that the system will be disconnected at the end of the establishment period. A pop-up requires substantial piping since it is a pressurized system, as well as deep piping below frost. USGBC\'s concern is that once a system like this is in place, it will be too easy to use on a regular basis. Hand watering and/or a drip irrigation system as you suggest are recommended for this application as they are less expensive upfront and much simpler to install and remove. The drip piping can be installed a bit below the surface so it is not visible, or covered with mulch to hide the pipe and thus give less opportunity for vandalizing. Also, there is less waste than installing PVC piping and pop-up heads and discontinuing use after a couple of years. Applicable internationally. " "None" "None" "X" "LEED Interpretation" "557" "2003-07-10" "New Construction" "Is the following acceptable for credit WE 1.2?\n\nINTENT:\nThe East Campus Private Development Project (ECPDP) is currently being constructed on Oak Ridge National Laboratory\'\'s (ORNL) campus. The design team has elected to construct the ECPDP over and around the existing ORELA 150 M Flight Tube facility (located partially underground) which will preserve the existing ORELA Flight Tube facility and conserve technical resources. The underground flight tube has an existing sump pit that discharges non-potable water (which seeps through the structure) into the storm water system. We intend to capture some of that water for landscape irrigation purposes. We have already incorporated highly efficient drip irrigation on one portion of the site, and have eliminated irrigation on the remaining portions of the site. Thus, the use of recovered water is minimal.\n\nWill this recovered water be acceptable as a ""non-potable"" water source?" "The project has proposed to divert water that would otherwise be wasted. The water will displace potable water used for irrigation. This approach is acceptable, but should be explained in a credit narrative. Applicable Internationally." "998" "None" "X" "LEED Interpretation" "6098" "2003-07-10" "New Construction" "Would the installation of hose bibs on the exterior of the building prevent us from claiming zero use of potable water for irrigation? Those hose bibs will supply water to clean loading docks, wash the dumpster, and provide water for maintenance and occasional cleaning of the exterior. There is no intention of using the hose bibs for irrigation because all plants are local and do not require irrigation except as a last resort in times of drought." "The installation of exterior hose bibs does not preclude a project from claiming zero potable water use for irrigation. The requirements for WE Credit 1.2 list as an option, ""do not install permanent landscape irrigation systems."" In general, hose bibs are not considered permanent landscape irrigation systems. Applicable internationally." "None" "None" "X" "LEED Interpretation" "5963" "2003-05-19" "New Construction" "This project inquiry applies to Water Efficiency Credit 3.2. For affordability, we installed faucets and water closet fixtures that satisfy the requirements for Credit 3.1 but at 80 psig water pressure their ratings do not satisfy the flow rates required by Credit 3.2. In order to achieve the required further reductions we are testing the use water saving devices such as water closet dams, to reduce the water usage for the 1.6 gallon per flush water closets. The amount of water per flush for the urinals were adjusted downward by the installing contractor using a valve that cannot be tampered by the general staff or public. Furthermore, the urinals are working fine at this lower flow rate. Our flow measurements at the faucets document that the actual flow rates enable the water systems to easily satisfy Credit 3.2. A major reason for this is that the water pressure at the fixtures is considerably less than 80 psig-we estimate it to be less than 40 psig. Essentially, the city water service and building water distribution system in this renovated building are playing an important role in lowering water usage. We also reduced construction costs and reused building materials by not replacing and upsizing the water service and building water distribution system. The first part of our inquiry is can we get credit for modifying fixtures (using toilet dams and adjusting internal valves) to enable them to consume less water. The second part of our inquiry is whether documented water flow measurements may be used in the LEED Application for Water Use Reduction Credits. We propose two forms of documentation: water flow measurements at the fixtures; tracking the building\'\'s water meter and comparing the total building water use against the Baseline usage. This approach is consistent with the LEED Existing Buildings approach of documenting actual water usage. " "Measured water use reduction figures can be used to document LEED credit achievement. In light of your building\'s 40 psig water pressure, manufacturer data may not provide a realistic baseline. The following conditions must be met by your project: 1) It is not acceptable to use manufacturers\' performance data as the baseline. The fixture performance baseline must be developed by testing the installed factory-calibrated fixture (in context of building water pressure) prior to any on-site adjustments. The fixture testing methodology must be compliant with an approved Measurement and Verification methodology (IPMVP or FEMP Measurement and Verification Guidelines). 2) The on-site adjustment or water savings strategy must be permanent. a) Flow control adjustment on urinals, as it is assumed that only building maintenance personnel can/would make such an adjustment, is considered permanent. Documentation must be provided that proves the adjusted fixture continues to provide acceptable performance. b) Water closet dams and non-tamperproof flow restriction devices (faucet and shower aerators) are considered non-permanent and easily tampered with/vandalized even if performance problems do not arise. 3) Water use reduction achieved through permanent on-site fixture adjustment/modification must be proven using the same methodology that was selected for development of the baseline case. Applicable internationally." "None" "None" "X" "LEED Interpretation" "5828" "2003-03-11" "New Construction" "The calculations were figured by LAndscape COnsultant and PA; The key to this credit is how the ""Baseline Case"" is determined. The ""Design Case"" takes into account the fact that the species planted are native and respond well to the Houston environment. The ""Baseline Case"" was calculated using a different turf grass species which would cover the entire landscaped area and would not be shaded by trees. We feel like this credit might be ""on the fence"" our team is a bit unsure of how to determine the subjective factors of the equation. For example, according to the Reference Guide, ""If a species does not require irrigation once it is established, then the effective [Species Factor] = 0 and the resulting [Landscape Coefficient] = 0."" Eventually, it will be possible to turn off this design\'\'s irrigation system once the plants are established, but should that be considered in the calculation if it takes longer than 1 year? What is the cut-off: 3 years, 5 years, 10 years?" "Although the project can take credit for selection of a native or drought tolerant species mix in the LEED calculator, the planting types should approximately correspond in both the baseline and the proposed strategy. That is, it is unreasonable to assume that the baseline is 100% turfgrass when the project clearly intends to include trees, shrubs, and planting beds. Irrigation efficiency is calculated on water delivered in the month of July of a typical year. With respect to LEED, the intention to eventually \'turn off\' an installed irrigation system is not the same installing an efficient irrigation system. Irrigation efficiency is also dependent on the type of irrigation system used. Drip irrigation or other low-flow systems can be used to achieve this credit, alone or in combination with appropriate species selection. It is up to the landscape designer to provide documentation that the species selected will not requre permanent irrigation once established. The generally accepted timeframe for temporary irrigation is one to two years. Applicable internationally." "None" "None" "X" "LEED Interpretation" "456" "2003-01-13" "New Construction" "WC2 Clarification\nPlease note that this question is related to Water Credit 1.1 and 1.2.\n10/23/2001 - Credit Interpretation RequestIf a well is installed at the site to extract groundwater for all irrigation needs, would this count for 2 points under WE Credit 1.1 and 1.2 since potable water would not be used at all for irrigation?\n10/23/2001 - Project Manager\'\'s RulingThe LEED Reference Guide (formatted version of July 2001) defines ""potable water"" on page 70 as, ""water that is suitable for drinking and is supplied from wells or municipal water systems."" Therefore, if the quality of the source is suitable for drinking, the intent of the credit is not met and the points would not be achieved.\n\nThis question is in response to an interpretation previously submitted by the team, Inquiry ID 0152-Wec12-102601. The response implied that 2 points could not be achieved since potable water is defined as ""water that is suitable for drinking and is supplied for wells or municipal water systems"". The water from this well will not be treated in any way, and is unsuitable for drinking.\n\nIn this case, can these 2 points be achieved if a letter is provided that confirms that the water is non-potable?" "The intent of this credit is to encourage water efficient or xeriscape landscaping practices, which require little to no irrigation. If, after such practices are implemented, irrigation is still necessary to maintain the landscape, then the applicant project can follow two paths for credit compliance: 1) high efficiency irrigation technologies; or 2) the use of non-potable water for irrigation purposes. The term \'potable water\' is used in this credit to differentiate ""recycled graywater"" (lavatory or shower water) and ""harvested rainwater"" (cisterns or collection ponds) from water drawn from ""receiving waters"" (rivers, lakes, aquifers). Although the local groundwater at the project may not be suitable for drinking straight out of the ground, it still represents an important source of potable water. Using groundwater as an irrigation source does not achieve this credit. Applicable Internationally." "None" "None" "X" "LEED Interpretation" "5996" "2003-01-13" "New Construction" "Water Credit 3 - Interpretation Request Our project is a student services center on a community college campus in California and includes a student store, staff offices, counseling centers,testing rooms, etc. There will be some full and part-time staff as well as various students temporarily occupying the building to take care of student business or shop at the student store, etc. We have reviewed the relevant pages in the reference guide, the CIRs, and the calculator and have not found answers to our question regarding this credit. We are wondering which faucet type (regular or metering) and corresponding flow rate requirement from the Energy Policy Act we should be using as the baseline for the sinks in our building. With some sinks, such as kitchen sinks, it seems obvious. Kitchen sinks are never metered so using the regular faucet with 2.5 GPF as the baseline makes since. Lavatory sinks on the other hand are sometimes metered and sometimes not metered, so we don\'\'t know which to use as our baseline. There is no code requirement in our area requiring that metering faucets be used on lavatories in our building type. Nor is this standard practice. We are however putting them in in order to reduce water use. Because there is no code requirement and because it is not ""typical"", we propose using the regular faucet (2.5 GPM) as our baseline and not the metering faucet (.25 gal/CY) as our baseline. The design case example in the reference guide (see page 89) uses the regular faucet as the baseline. Which we use makes a difference in the water savings achieved. We very much appreciate any assistance and insight you can offer. Let me know if you need additional information from us. Thank you, Kathleen Smith" "The LEED 2.0 Reference Guide states: ""The baseline case is calculated in the same manner as the design case except that [for the baseline case] ALL fixtures are assumed to be standard fixtures that comply with the Energy Policy Act of 1992. Also, [in the baseline case] automatic sensors are not used on any fixtures and there is no gray water use."" Furthermore, the LEED 2.0 Reference Guide shows a conventional lavatory flow rate to be 2.5 GPM for baseline calculations, which is the value you should use in your baseline calculations. For the design case, use the flow rates documented in manufacturer\'s literature. Note that Table 4 has a column for ""Auto Controls"" to incorporate your metered flow controls for the design case. Applicable internationally. " "None" "None" "X" "LEED Interpretation" "6010" "2002-10-21" "New Construction" "We are currently working on a project sited on a university campus. This university has a campus-wide wastewater (sanitation sewer, not storm water) collection and reclamation system in place. Our project is connected to this system. Storm water is collected from the roof of the project building and stored in a cistern. This collected storm water will be used solely for flushing toilets and urinals. The use of these two strategies seems to apply to every credit in the ""Water Efficiency"" section. In WE 1.1 and 1.2, the intent is to ""Limit or eliminate the use of potable water for landscape irrigation"". This intent is met by the campus-wide system above. Since a campus-wide system is already in place, it would be of little or no benefit to create a separate site system and we feel we should not be penalized for this. Project money has been utilized to connect the project to the university system. Will this system allow us to earn WE credits 1.1 and 1.2? We are currently incorporating a rainwater collection cistern into the project for flushing toilets and urinals (at least 50% of building water needs). Would this strategy alone earn us WE credits 3.1 and 3.2? The intent is to ""Maximize water efficiency within buildings to reduce the burden on municipal water supply and wastewater systems."" The rainwater cistern eliminates the need for municipal water. It would appear that this also meets the intent of WE credit 2; ""Reduce generation of wastewater and potable water demand" "Captured rainwater or recycled site water can contribute to achieving all of the water credits. To achieve credit for reduction of landscape water use, the landscaping/irrigation system must be designed to use water efficiently, or you must demonstrate that the rainwater collection system supplies enough water to the irrigation system to meet the calculated irrigation water demand for the month of July. See the LEED Reference Guide for calculation methodology. If your campus-wide wastewater system provides non-potable reclaimed water to the building\'s irrigation system at the levels required by LEED, you can earn the points for WE credits 1.1 and 1.2. Rainwater harvest can be used to offset potable water used for sewage conveyance and thereby achieve credit WE credit 2. Graywater supplied from the cistern can be applied on its own, or in combination with low-flow fixtures, to attain the 50% potable water reduction required for this credit. The calculation must be applied to fixtures which discharge into the sewer; landscape water use/savings does not count toward credit WE 2. Use the LEED calculator for assistance in performing these calculations. To achieve credit WE credit 3.1, the use of the roof cistern system must provide 20% of the total aggregate (in-building - excluding irrigation) water usage. Water conserving fixtures that use less water than EPACT requirements can be used in combination with rainwater harvesting to achieve this credit. Use the LEED calculator for assistance in performing these calculations. WE credit 3.2 - Use of the roof cistern system must provide 30% of the total aggregate (in-building, excluding irrigation) water usage. Water conserving fixtures that use less water than EPACT requirements can be used in combination with rainwater harvesting to achieve this credit. This could be important if the rainwater system doesn\'t meet the water use reduction requirements alone. Use the LEED calculator for assistance in performing these calculations. Note, if WE 3.2 is attained, then credit is also given for WE 3.1. Applicable internationally. " "None" "None" "X" "LEED Interpretation" "5740" "2002-10-07" "New Construction" "Our project is a student services center on a college campus in California and includes a student store, staff offices, counseling centers, testing rooms, etc. There will be some full and part-time staff as well as various students temporarily occupying the building to take care of student business or shop at the student store, etc. We have reviewed the relevant pages in the reference guide, the CIRs, and the calculator and have not found answers to our questions regarding this credit. 1. How do we determine the number of male occupants and female occupants for the purposes of Water Credit 3.1, 3.2 and 2? Do we use the same criteria and formula laid out in Site Credit 4? And how do we account for short-term visitors to the building (e.g. someone shopping in the student store or stopping in for an appointment or to pick up forms from one of the offices)? 2. What criteria, standards, or assumptions do we base the ""daily uses"" and ""duration of use"" per fixture type for each gender on? The reference guide provides tables and criteria for the flow rates of various flush and flow fixtures for determining the base case and the design case, but does not seem to address ""daily uses"" and ""duration."" We look forward to your specific direction on these questions. " "1. Water use is based on building occupants. For this type of facility, determine the average building occupancy based on visitors and full/part time staff. Use this number in water use calculations. The ratio of male to female occupants can be estimated based on student population data or use 50:50. Outline any assumptions made about visitor use in the project narrative. Visitors use restrooms, so they should be included in water use calculations (though you may assume a lower use rate per visitor than per staff member). The exclusion of short-term visitors from Site credit 4 does not apply. However, short term visitors are not required to be included in the number of occupants that use showers (if provided) nor in the related LEED calculation. 2. There are no set criteria for determining daily use or duration of use. Applicants can estimate both of these items based on the project and occupants. Water audits by the college or similar facilities may provide a reference for the applicant, but are not required for LEED documentation. The LEED Reference Guide provides some sample calculations of fixture uses per day and duration that you can use as a guideline. These assumptions are based on full time occupants, so you will need to make assumptions for part time occupants. Daily uses and duration must be the same in both the Baseline and Proposed Cases. Applicable internationally." "None" "None" "X" "LEED Interpretation" "5853" "2002-10-07" "New Construction" "The existing source of potable water for our project is ground wells. Under Credit 3-Intent: "" burdan on Muncipal water supply needs to be reduced."" Under Requirement (Credit 3.2): we need to \'\'exceed the potable water use reduction by 30% over baseline. On page 70 of the LEED Reference Guide defination of potable is \'\' water that is suitable for drinking and is supplied from wells or munciple water systems\'\'. Our project has existing wells as a source of potable water. We are employing stratergies that use 30% less potable water than the baseline calculated for the building after meeting Energy Policy Act of 1992 fixture performance requirements. Would the project be eligible for this credit as the source of water are existing wells?" "The intent of this credit is to \'maximize water efficiency within buildings to reduce the burden on municipal supply and wastewater systems.\' The LEED version 2.0 Reference Guide (June 2001) states on page 85 that \'the reduction of potable water use in buildings for toilets, shower heads, and faucets reduces the total amount withdrawn from rivers, streams, underground aquifers and other water bodies.\' Reducing well water used in the building will also reduce the amount of water taken from local water bodies and reduce the burden on wastewater systems. Therefore the project\'s water savings can qualify for this credit whether they are using municipal water or well water. Applicable internationally." "None" "None" "X" "LEED Interpretation" "6000" "2002-06-28" "New Construction" "We are assisting a university that is eager to obtain LEED certification for a new laboratory building. This laboratory will use equipment that requires water cooling. Currently, local and state regulations allow for the use of single-pass cooling, in which water is used to cool the equipment and discharged into the outgoing wastewater line. The project\'s MEP has designed a water-cooling loop that will allow the equipment to be cooled with chilled water that will pass through a heat exchanger and be re-circulated so that it is not being constantly pumped and discharged following only one pass. With this set up, water usage is reduced by over 30% and waste water output is reduced by over 50%. We want to confirm that this water savings is applicable to not only the WE Credit 3, but to the WE Credit 2 as well." "----------------------------------------------- NOTE: THIS RULING HAS BEEN OVERTURNED BY WEc2 RULING DATED 3/9/04. Process water is not to be included in WEc3 credit calculations, either. Instead, apply savings towards a possible innovation credit. ---" "None" "None" "LEED Interpretation" "5875" "2002-05-17" "New Construction" "The LEED V2.0 Reference Guide dated June 2001 does not clearly indicate whether a project must include Cooling Tower water use or commercial kitchen equipment when performing the calculations for Water Credit 3-Water Use Reduction. Page 98 of the reference guide suggests that a project consider specifying efficient cooling towers and employing water recovery systems for cooling tower make-up. However, the calculation tables and the LEED Calculator do not make any reference to Cooling Tower water demands or commercial kitchen equipment. Since cooling towers in commercial office buildings generally use at least fifty percent of the water consumed by these building types, it would seem that requiring their inclusion in this Water Efficiency Credit 3 would discourage most projects from pursuing this credit. In addition, measures to increase the efficiency of cooling tower water use generally results in a greater consumption of electricity except for rain water reuse, which is a strategy with a very high first costs. Furthermore, LEED References the 20% and 30% reductions with respect to the Energy Policy Act of 1992 (EPACT) Fixture Performance Requirements. EPACT does not address cooling towers. Based on the issues raised above, the design team is of the opinion that cooling tower water use is not to be included in the calculations for determining the 20% or 30% reduction in water use. Does the LEED V2.0 Rating system require a project to include Cooling Tower water when determining the percentage reduction of potable water used in a building for Water Efficiency Credit 3.1 and 3.2? In addition, this project includes a large cafeteria capable of serving 200+ people. The equipment used in the kitchen of the cafeteria is considered a ""process load"" in the LEED Optimize Energy Performance Credit, and thus is not included in the energy reduction calculations. Does this classification as a ""process load"" also apply to the LEED Water Efficiency Credit and thus exempts the dishwashing equipment to be exempt from the Water use reduction calculations?" "This credit requires listing fixtures that are necessary for the occupancy of the building, such as for drinking water and conveying sewage. The Technical Advisory Committee agrees that the cooling tower and dishwasher water loads are process loads, and are not required to be included in the calculations. Applicable internationally." "None" "None" "X" "LEED Interpretation" "194" "2002-02-14" "New Construction" "Re: LEED WE Credits 1 and 3 We are presently working on the landscape design for a LEED registered project. As part of the landscape, we are installing an outdoor fountain. The fountain system re-circulates its water, but will automatically back flush the filter at a rate of 75 GPM once or twice per week. The back flush uses potable water. Rather than direct this water into a waste line, we intend to pipe it into the 14,000-gallon rainwater harvest tank for use in our low volume drip irrigation system. Our calculations show that the amount of rainwater collected on the site will not provide adequate volume to establish the trees. Supplemental hand watering would be required for an establishment period of two to three years. This approach will eliminate the need for potable water for irrigation during establishment. At the end of this period, the trees will continue to benefit from the additional water during our annual dry season. Would the fountain back wash water described be considered \'recycled site water\' as outlined in WE Credit 1? Must the outdoor fountain back flush water be counted in calculations of building water use in credit 3?" "NOTE: This LEED Interpretation ruling was overruled by subsequent NCv2.0/2.1 WEc3.1 and WEc3.1 LEED Interpretations which state that only fixtures regulated by EPAct of 1992 should be included in WEc3 calculations. Adding a water feature to a project does not address reducing the demand for irrigation water. You have stated that the landscape design needs supplemental watering beyond available rainfall at the project location. The scheme is using potable water for irrigation, but it first runs the water through the fountain for a design effect. The potable water used in the fountain system should be included in the Water Efficiency Credit 3.1 and 3.2 calculations. Applicable Internationally" "None" "None" "X" "LEED Interpretation" "6032" "2002-01-03" "New Construction" "We are taping a stormwater culvert near our site and treating the water for use as non-potable irrigation water. We are providing water to 51,330 s.f. of landscaped area and have a planter designed for a 6th floor balcony/plaza area which is 123 s.f. Our question is this, In your Design Approach section you use the term ""site landscape"" can we assume that our planter is not site landscape and use potable water for this area only?" "Yes, you can exclude the planter area from the site landscape, as it represents only 0.25% of the total irrigated area. The water use for the planter should be included in the calculations for Water Use Credit 3.1 and 3.2 that apply to water use within buildings." "None" "None" "LEED Interpretation" "281" "2001-10-23" "New Construction" "If a well is installed at the site to extract groundwater for all irrigation needs, would this count for 2 points under WE Credit 1.1 and 1.2 since potable water would not be used at all for irrigation?" "The LEED Reference Guide (formatted version of July 2001) defines ""potable water"" on page 70 as, ""water that is suitable for drinking and is supplied from wells or municipal water systems."" Therefore, if the quality of the source is suitable for drinking, the intent of the credit is not met and the points would not be achieved. Applicable Internationally." "None" "None" "X" "LEED Interpretation" "5453" "2001-09-24" "New Construction" "Rainwater harvesting is NOT possible in Phoenix, Arizona. It has been determined that there is sufficient water being discharged from the cooling tower that can be treated and stored and used to provide 100% of the water required for the landscaping for this project. Calculations will be provided with the application submittal to substantiate this reuse of wastewater. Does the use of the water discharge from the cooling tower meet the intent for WE Credits 1.1 and 1.2? Would this method of reusing water be considered for an innovation credit in addition to receiving Credits 1.1 and 1.2 since it currently is not addressed by LEED?" "Utilizing cooling tower discharge can be considered using \'recycled site water\' and would qualify for this credit. Since the cooling tower discharge will apply to these credits it would not also qualify for an innovation point. Applicable Internationally. " "None" "None" "X"