Entry Type ID Date Applicable Rating System Primary 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) "LEED Interpretation" "10096" "2011-08-01" "New Construction, Core and Shell, Schools - New Construction, Retail - New Construction, Healthcare, Data centers - New Construction, Hospitality - New Construction, Commercial Interiors, Retail - Commercial Interiors, Existing Buildings, Schools - Existing Buildings, Retail - Existing Buildings" "This project is a renovation of an existing building on a university campus. This building is one of a series of buildings constructed in the early 1960\'s, and the University is attempting to maintain the character and cohesiveness of the campus by preserving the existing structures and facades. Preserving the buildings also contributes to our sustainable design efforts, but it has resulted in an issue with the prerequisite for indoor air quality. The basement and first floor levels are mechanically ventilated in accordance with ASHRAE 62.1, and do not present a problem. However, running ductwork to the upper floors did prove problematic, so the design team is relying upon natural ventilation for the second and third floors. After calculating the window ventilation areas, all but three of the rooms comply with ASHRAE 62.1 for natural ventilation. The three rooms in question obtain 74%, 77% and 78% of the required ventilation area for operable windows.\n\nIn order to meet University requirements and LEED Criteria all windows will be replaced with new, energy star models, to match the size and appearance of the existing windows. As previously mentioned, these new windows will generally provide 100% opening requirements, except in the three cases noted.\n\nIt is the University\'s intent, as the Authority Having Jurisdiction, to grant a waiver for the minimum ventilation requirement in only these three rooms, thereby permitting the maximum use of the facility, while maintaining the historic appearance of the building.\n\nThe University has therefore requested an interpretation from USGBC that this waiver for reduced ventilation requirements will be acceptable for obtaining LEED Certification for these facilities." "The applicant is requesting a waiver from the ASHRAE 62.1-2007 Section 5.1 natural ventilation prescriptive requirements for three rooms within the existing building. The new window areas are insufficient to meet the prescriptive requirements and are specified and installed per university requirements. ASHRAE 62.1-2007 exempts engineered natural ventilation systems when approved by the authority having jurisdiction. The natural ventilation system, as described, does not appear to be an engineered system. In this case, the prescriptive requirements could not be waived." "None" "None" "LEED Interpretation" "1523" "2009-02-10" "New Construction, Schools - New Construction, Commercial Interiors, Core and Shell, Existing Buildings" "RE: an engineered natural ventilation method to a production/storage area. The prescriptive method in ASHRAE Std 62.1 which requires all natural ventilated area to be within 25 feet of operable wall or roof openings. Instead of the prescriptive method, we propose that the normal practice in Thailand, using wind operated roof cowls, to be adopted as the engineered natural ventilation method. The effectiveness of the method is proven in many other similar buildings in the same industrial park and it is an approved/acceptable design method to IEAT, whom is the local authority having jurisdiction to approve all building and building services design. In tandem with the above natural ventilation option requires the building flush-out to be performed using outdoor air to maintain an internal temperature of at least 60oF (15.6 oC) and relative humidity no higher than 60%. From the ASHRAE data for Annual Dehumidification Design Conditions (see Attachment 3), the design condition for Bangkok is 30.2/26.7 oC which is equivalent to an outdoor relative humidity of 76%. The naturally ventilated spaces which form the majority of the building area do not have any means for dehumidification and as such, will likely to have the same relative humidity as the outdoor condition of 76%. We are unsure if this applies to this application as to reduce the relative humidity to less than 60% during flush-out period while the occupied condition thereafter will be likely to be higher than 60%. Therefore in the space which is naturally ventilated and not heated or cooled, is it necessary to maintain the temperature and humidity requirements stipulated in the credit language during flush-out? Will these approaches be acceptable with regards to our natural ventilation proposal?" "EQ Prerequisite 1, Minimum IAQ Performance, requires that naturally ventilated buildings comply with ASRHAE 62.1-2004, paragraph 5.1. The exception to paragraph 5.1 states that an engineered natural ventilation system approved by the authority having jurisdiction over the project does not have to meet the requirements of 5.1.1 and 5.1.2. If the local authority follows ASHRAE 62.1-2004, or an equivalent standard, then their approval of the engineered natural ventilation system as meeting the ventilation standard is sufficient to meet the intent of this prerequisite. The question regarding the building flush-out under EQ Credit 3.2 needs to be addressed by a separate CIR. The project is instead encouraged to use Option 2, Air Quality Testing, to demonstrate compliance with this credit. Applicable Internationally, Thailand." "None" "None" "X" "LEED Interpretation" "1641" "2007-01-02" "New Construction, Schools - New Construction, Commercial Interiors, Core and Shell, Existing Buildings" "Our LEED application is for a high-rise residential building (over 40 stories), located in downtown Los Angeles, with underground parking. The Indoor Environmental Quality prerequisite for minimum IAQ specifies ASHRAE 62-2004 as a requirement, or the most stringent local design guideline. We are concerned with parkade ventilation, as ASHRAE 62-2004 specifies 1.5 CFM/ft2 as a design level for this type of space. The State of California building code has a basic requirement for 14,000 CFM times 2.0% of the total number of stalls (rounded up). We have experience designing parkade structures in Vancouver under the CaGBCs LEED Rating system (version 1.0, 2004). In these cases, we have utilized an alternative compliance path to achieve the minimum IAQ prerequisite 1. This compliance path was to follow the British Columbia Building Code, which on its basis requires 0.75 CFM/ft2, and to implement CO sensors to bring in more outdoor air as required to meet the CO levels as shown in ASHRAE 62-2004, Table 1. This strategy achieves a healthy IAQ level for the space according to ASHRAE, and complies to the local building code. For the parkade spaces of our building, will we meet the intentions of the prerequisite if we comply with the design requirements of the State of California Building Code and implement CO sensors in an identical manner as described above to comply with ASHRAE?" "Your proposed method to comply with this prerequisite must comply with ASHRAE Standard 62.1-2004 requirements or the local code, whichever is more stringent. Standard 62-2001, which does not apply to NCv2.2 projects, required 1.5 cfm/ft2 outdoor air) for parking garages and allowed the use of contaminant sensors (e.g., CO sensors) to control outdoor airflow. Standard 62.1-2004, however, requires 0.75 cfm/ft2 (exhaust air) and neither requires nor prohibits the use CO sensors to control exhaust airflow. The methodology you described above meets the requirements of standard 62.1-2004, and the state of California Building Code requirements; therefore the methodology is acceptable." "None" "None" "LEED Interpretation" "1765" "2007-05-18" "New Construction, Existing Buildings, Commercial Interiors, Core and Shell, Schools - New Construction" "The building is a 144 unit apartment building in the District of Columbia. The proposed design would utilize natural ventilation from the exterior windows and doors with operable areas equal to or greater than 4% of the floor area with all areas to be ventilated permanently open to the rooms with operable windows or doors. However, all spaces to be ventilated are not within 25 ft. of the operable wall openings. The prerequisite requires meeting ASHRAE 62.1 2004 Sections 4-7. Section 5.1 of the ASHRAE standard has an exception that states ""An engineered natural ventilation system when approved by the authority having jurisdiction need not meet the requirements of section 5.1.1 and 5.1.2."" ASHRAE 62.1-2004 does not define what an ""Engineered Natural Ventilation"" system is. The system we propose above meets the requirements of the 2003 International Mechanical Code accepted by the local jurisdiction (the District of Columbia). Does it therefore qualify for the exception in section 5.1 of ASHRAE 62.1-2004 -- and meet the LEED prerequisite?" "The project may use natural ventilation as the only source of outside air only if it can demonstrate, using acceptable engineering calculations or multi-nodal bulk airflow simulation, that under still air conditions, the units will satisfy the requirements of Appendix E Table 2 for residential facilities." "None" "None" "LEED Interpretation" "1888" "2007-09-24" "New Construction, Existing Buildings, Commercial Interiors, Core and Shell, Schools - New Construction" "Our project is a new 7-story, 120-unit, residential building for retired seniors in Massachusetts. The apartments will have operable windows in the living rooms and bedrooms, with openable areas significantly greater than 4% of the floor area, and kitchens that are permanently open to the living rooms. However, some apartments will be deeper than 25 feet. (The worst case scenerios would likely be 29 feet deep for a non-corner unit or 38 feet deep for a corner unit.) Furthermore, some units will have interior bathrooms and walk-in closets that are not permanently open (as defined by ASHRAE 62.1 2004) to the spaces with windows. The living units will have heat pumps with air handlers that offer heating, cooling, or fan-only mode. The air handlers will intake return air, rather than outside air, but the air intake will be within 25 feet of the operable windows, meaning a portion of the air would be fresh when the windows are open. The air handlers would then distribute ducted supply air to each major room, not including bathrooms and walk-in closets. Also, the public corridors will be positively pressurized providing make-up air to the apartments via door under-cuts. The bathrooms will have occupant-controlled exhaust fans. 1. Is it possible that this design as-is meets the outdoor air ventilation requirements of ASHRAE 62.1 2004? If so, with such a complex air delivery model, how do we perform the calculations, if any, to prove this for LEED? 2. If it sounds like our design does not meet ASHRAE 62.1 2004, could either of the following solutions bring us into compliance? And again how would we perform the calculations, if any? a. Installing occupant-controlled paddle fans on the ceilings of the rooms with windows. b. Installing continuous bathroom exhausts (or bathroom exhausts on a timer) to draw fresh air deeper into the space. The bathrooms are usually located at the furthest points from the operable windows. 3. If none of the above solutions sound like they meet ASHRAE 62.1 2004, do you have any suggestions other than making the living units less than 25 feet deep? By the way, we would like to keep the units negatively pressurized with respect to the public corridors to meet the Environmental Tobacco Smoke prerequisite. One final question. Under ASHRAE 62.1 2004 are apartment kitchens required to be exhausted to the outdoors? If so, is there any way the bathroom exhausts could satisfy this requirement?" "This CIR poses three questions. The first question is whether the design described in the Credit Interpretation Request, where some spaces fall further than 25 feet from an operable window, meet the ASHRAE Standard 62.1-2004 minimum ventilation requirements. Based on a previous CIR (EQp1 Ruling date 5/15/2007) if the HVAC system is re-circulating air only, then the unit is considered naturally ventilated provided that it meets the requirements laid out in section 5.1 of the Standard. If all requirements for a naturally ventilated space are met then that space complies with the requirements of the Standard for naturally ventilated spaces. If a space is further than 25 feet from an operable window it cannot be considered as naturally ventilated. Since the depth of some residential units in this project is more than 25 feet from operable windows, it is possible that not all spaces in this project can be considered naturally ventilated. In order to ensure compliance with the ASHRAE Standard\'s minimum ventilation requirements for mechanically ventilated spaces, the project team will have to refer to Appendix E of the standard which applies to residential and healthcare projects. Appendix E provides guidance on adequate ventilation rates through air changes per hour and/or cfm per person outdoor air ventilation rates (for living areas), and cfm exhaust (for bathrooms and kitchens). Note that walk-in closets are excluded from the Standard, since they cannot be considered as ""occupiable space"" by the Standard\'s definition (page 4 of ASHRAE Standard 62.1-2004). The design described does not comply with the requirements of Appendix E, since the ventilation system described is re-circulation only. Calculations to demonstrate compliance with ASHRAE Standard 62.1-2004 for naturally ventilated spaces will include showing adequate operable window opening area, and/or permanently open area to another space that is naturally ventilated (the total areas of both spaces have to be included in the 4% operable window opening area calculations). Calculations to demonstrate compliance with ASHRAE Standard 62.1-2004 for mechanically ventilated spaces in residential projects, will include showing air changes per hour and/or cfm per person outdoor air ventilation rates (for living areas), and cfm exhaust (for bathrooms and kitchens), according to the requirements of Appendix E. The second question proposes two methods to ensure compliance with ASHRAE Standard 62.1-2004 minimum ventilation rates in spaces that cannot be classified as naturally ventilated. The first proposed method, installing occupant-controlled paddle fans on the ceilings of rooms with operable windows, will not ensure adequate ventilation in spaces that are outside of the 25 feet range from the operable window. Even if the project team can demonstrate that adequate air changes per hour has been achieved in those spaces, this requires the paddle fan to be constantly in operation. The second proposed method, installing continuous bathrooms exhausts (or bathroom exhaust on a timer), will only ensure that the bathrooms will meet the requirements of Appendix E and will not have an impact on other spaces. The other option would be to provide the required amount of fresh air into occupiable areas more than 25 feet from the windows, in order to meet the requirements of Appendix E. The third question is asking whether under ASHRAE 62.1 2004, kitchens are required to be exhausted to the outdoors. If the kitchens qualify as naturally ventilated spaces, and there are no special requirements for combustion air or removal of combustion products, then there is no exhaust requirement. If the kitchens do not qualify as naturally ventilated spaces, then they will have to meet the exhaust requirements laid out in Appendix E: 100 cfm intermittent or 25 cfm continuous exhaust." "1960, 1969, 2150, 2208, 5096, 5259, 5294" "None" "LEED Interpretation" "1951" "2007-11-27" "New Construction, Schools - New Construction, Commercial Interiors, Core and Shell, Existing Buildings" "The project is 230 sq. ft including two toilet rooms, two lavatory rooms and an outdoor covered bar (including a refrigerator, waste and recycling recptacles and seating). The building will be used by approximately 80 to 100 people per day fluctuating during the summer and winter seasons. The question is: may this project obtain this prerequiste and will it qualify in general to obtain LEED certification assuming it met the required points? Specifically, public toilets are referenced within ASHRAE 62 in Table 6-4, Minimum Exhaust Rates. Additionally, bathrooms are included in the scope of this Standard per 2.1. Furthermore, the building meets the natural ventilation requirements along with the state energy code. In summary, I am not able to find any information within the reference guide preventing this project from obtaining LEED NC certification. It is a commercial permitted project per the Authority Having Jurisdiction. On page 14, Section III, paragraph A of the reference guide, it clearly does not prohibit certification of a restroom facility. Currently the project is anticipating at least Certified with Silver potential, therby proving LEED NC applicability. Thank you for your thoughtful consideration." "The CIR is inquiring as to whether a restroom facility may qualify for EQp1 and thus be eligible for LEED certification. The applicant is correct in their mention of the Reference Guide - all commercial buildings are eligible for LEED-NC certification. In order to show compliance for EQp1, the project must demonstrate that it meets the requirements of ASHRAE 62.1-2004, Sections 4 through 7 or equivalent. For this project, this verification will include documentation showing that it meets the exhaust air requirements of the standard as well as providing either the Ventilation Rate Procedure for any applicable mechanically ventilated spaces or documentation demonstrating compliance with paragraph 5.1 for naturally ventilated spaces. Applicable Internationally." "None" "None" "X" "LEED Interpretation" "1960" "2008-01-10" "New Construction, Schools - New Construction, Commercial Interiors, Core and Shell, Existing Buildings" "Our project team wants to verify an acceptable compliance path for achieving the EQp1 Minimum IAQ Performance in a mid-rise apartment project with recirculating kitchen exhaust and operable windows. We have reviewed the CIR ruling dated 9/24/2007 and we are requesting clarification on part of this ruling. The ruling states which calculations must be presented to prove that a space is naturally ventilated: ""Calculations to demonstrate compliance with ASHRAE Standard 62.1-2004 for naturally ventilated spaces will include showing adequate operable window opening area, and/or permanently open area to another space that is naturally ventilated (the total areas of both spaces have to be included in the 4% operable window opening area calculations.)"" Our question pertains to the second part of that statement. We are trying to understand how to interpret the code in the following instance. If a kitchen without an operable window and a recirculating fan is 1. immediately adjacent to a living room with an operable window AND 2. that operable window is more than 25\' away from where the kitchen begins AND 3. the space between the kitchen and the living is completely open- that is, the floor plan is ""open"" and there are no obstructions between the ""kitchen"" and the ""living room""- May the kitchen in this case be considered naturally ventilated?" "The applicant is requesting clarification regarding the applicability of the natural ventilation definition to a kitchen. The applicant must demonstrate that the kitchen area referenced is able to meet the requirements of section 5.1.1 of ASHRAE 62.1-2004 specifically the section that states ""Where interior spaces without direct openings to the outdoors are ventilated through adjoining rooms, the opening between rooms shall be permanently unobstructed and have a free area of not less than 8% of the area of the interior room nor less than 25 sq.ft. ( 2.3 sq.m.) ""." "1888, 1969, 2150, 2208, 5096, 5259, 5294" "None" "LEED Interpretation" "1969" "2007-11-28" "New Construction, Schools - New Construction, Commercial Interiors, Core and Shell, Existing Buildings" "We are designing an archival storage facility for The Smithsonian Institution (SI) in Suitland, MD to house a variety of their collections including skeletal samples, artwork, paintings, biological samples, mineral cores, meteorites, negatives, magnetic film, etc. While we are providing outside air in compliance with the 2006 International Mechanical Code and ASHRAE 62.1-2004 in all other spaces, there are several refrigerated boxes (ranging from a hundred square feet to several thousand square feet) with temperatures between -4 and 55 degree F. SI practice forbids outside air supply to cold boxes based on their experience. The contents of the cold boxes are infrequently used, and given SI\'s mission of protecting national treasures, the institution has determined that the reliability of the boxes is better ensured by eliminating the complication of supplying these storage devices with OA. The Smithsonian Institution has assured us that no hazardous off-gassing will occur within the refrigerated boxes. SI intends to add small filters in the cold rooms to absorb odor. Question: Based upon the Ruling dated 9-24-07 for the CIR dated 8-30-07 under INDOOR ENVIRONMENTAL QUALITY: Minimum IAQ Performance: Please confirm that the cold boxes ""are excluded from the Standard, since they cannot be considered as ""occupiable space"" by the Standard\'s definition (page 4 of ASHRAE Standard 62.1-2004)""." "The CIR is requesting confirmation that their cold boxes are excluded from the referenced standard as they do not qualify as occupiable spaces. The spaces, as described, do not meet the ASHRAE 62.1-2004 definition for an occupiable space. It should be noted, however, that spaces which do not qualify as occupiable spaces are not necessarily excluded from Ventilation Rate Procedure (VRP) calculations. In this case, the cold boxes may be excluded from the outside air requirements of the Ventilation Rate Procedure provided that the project can confirm that people will occupy these spaces infrequently and for short periods of time. If people are spending extended periods of time within the spaces, or visiting them frequently, they must be provided with adequate ventilation. Additionally, the project should submit confirmation that there are no significant sources of indoor air contaminants within the spaces. If indoor air contaminant sources are identified, steps must be taken to limit exposure from these contaminants." "1888, 1960, 2105, 2208, 5096, 5259, 5294, 2150" "None" "LEED Interpretation" "2043" "2008-02-12" "New Construction, Schools - New Construction, Commercial Interiors, Core and Shell, Existing Buildings" "Description We are planning to construct an apparel factory for LEED certification. The planned factory will have 1000 sewing machines and few finishing equipments among others. The entire space will be air conditioned to maintain ASHRAE comfort levels. The occupation density is 20-25 persons per 1000 square feet. Proposal Since there is no specified category in ASHRAE 62.1-2004 \'Ventilation for Acceptable Indoor Air Quality\' for apparel industry, we are proposing to use \'data entry\' category listed under office buildings which is similar (200W sewing machine with operator seated similar to data entry). This allows 5cfm per person with 0.06cfm per square feet. Please rule on the acceptability of this approach." "The CIR is asking for verification that they have selected the appropriate Occupancy Category for their project, given that it does not fall precisely within the categories listed in ASHRAE 62.1-2004. ASHRAE instructs that if the occupancy category for a proposed space or zone is not listed, the requirements for the listed occupancy category that is most similar in terms of occupant density, activities and building construction shall be used. It is up to the discretion of the design team to select the most appropriate alternative. It would be beneficial to the LEED reviewer if, included with the prerequisite submission, the applicant provides an explanation of their rationale for the selection. Applicable Internationally. " "None" "None" "X" "LEED Interpretation" "2054" "2008-03-25" "New Construction, Schools - New Construction, Commercial Interiors, Core and Shell, Existing Buildings" "We conform to most of the requirements of EQ Prerequisite 1 but it was found that some of them are not applicable to Hong Kong. In Section 5 of ASHRAE 62.1-2004 Systems and Equipment, it requires the installation of dehumidification (5.10), finned-tube coils and heat exchangers (5.12) and humidifiers and water-spray systems (5.13). Due to the hot and humid climate in Hong Kong it is not common to install them in the building and it is considered not environmentally sound to install them if they are not going to be used during the operation of the building. As thus, we ask for waiver for this requirement." "The applicant is requesting a waiver from the compliance requirements of sections 5.10, 5.12 and 5.13 of ASHRAE 62.1-2004. All the requirements listed in ASHRAE 62.1-2004 section 5, Systems and Equipment, are not anticipated to be applicable to all projects. All the possible requirements have been listed, and only for those applicable to the specific project is compliance required. If the project does not have any of the specialized systems listed in the requirements, then the applicant should list those systems that have been installed and demonstrate compliance with those systems only. Applicable Internationally." "None" "None" "X" "LEED Interpretation" "2064" "2008-03-25" "New Construction, Schools - New Construction, Commercial Interiors, Core and Shell, Existing Buildings" "This CIR is in reference to ventilation design for a mid-rise residential building in New England. There is a central corridor on each floor of the building, with residential unit entry doors on both sides of the central corridor. All residential unit kitchens include resident-controlled 100 cfm exhaust fans, ducted to the building exterior. 1. At the entry door from the central corridor to most of the residential units, a small entryway exists that is permanently open to the unit kitchen (opening to the kitchen is at least as large as a standard doorway, but no door exists, so there is no way to physically separate the spaces). In some residential units, a portion of the entryway floor space (typically 3 square feet - 8 square feet of floor space) is more than 8 m from a window-wall. In these cases, since the entryway is permanently open to the kitchen, can the unit entryway be considered part of the kitchen, and thus meet the requirements of ASHRAE 62.1-2004 through the inclusion of the kitchen exhaust fan? 2. A minority of residential units in the building (8%) include entry corridors, rather than small entryways, and a portion of the floor space of those entry corridors is greater than 8 meters from a window wall. In those cases, the unit entry corridors will be mechanically ventilated by delivering ducted air from a continuously running 100% fresh-air common-area corridor make-up air HVAC system to the residential unit entry corridors. Can we consider the portions of the entry corridors that are within 8m of the window walls to be mechanically ventilated, and thus base the amount of air delivered to the entry corridors on a minimum of 0.35 ACH for only the portion of the entry corridors that are more than 8 m away from a window wall?" "The applicant is requesting clarifications on the application of ASHRAE 62.1-2004 for mid-rise residential building in New England. This is a two part CIR and the ruling is provided to address each of those parts respectively. 1. For kitchen areas please refer to Table E-2 in ASHRAE 62.1-2004. This building would be considered mechanically ventilated as per the information provided in the CIR and based on the 100 CFM manually controlled kitchen exhaust. Areas not within 8 m of operable windows must be provided with 0.35 ACH of the floor area of outside air. The applicant may account for the additional outside air in the kitchen exhaust and increase the kitchen exhaust volumes. 2. Yes. The spaces could be considered part of the entry corridor as long as those spaces meet the requirements for minimum outside air provided (0.35 ACH for the applicable floor area and not less than 15 CFM per person in the unit). This ruling is completely dependent on the applicant meeting all the other requirements of ASHRAE 62.1-2004 sections 4 through 7 and Appendix E. In addition to the 100 CFM exhaust, the applicant has to provide minimum exhaust flow rates as per table E-2. It would be helpful to please provide the following with your LEED Submittal to ensure that the review team has a clear picture of the ventilation air flows: 1. Line drawing schematic for the ventilation air flows in the project. 2. Calculations clearly outlining the spaces that qualify under the 0.35 ACH rule versus areas that qualify under section 5.1 or the 100 CFM exhaust rates. 3. Floor plans for a typical floor with the components of the ventilation system clearly marked and highlighted." "None" "None" "LEED Interpretation" "2098" "2008-05-13" "New Construction, Schools - New Construction, Commercial Interiors, Core and Shell, Existing Buildings" "This project consists of 7 buildings in the United Arab Emirates, on the Persian Gulf. Each of the buildings has from 5-21 workshops for repair of boats, engines, transmissions, etc. There is no heating in the buildings and they are all cooled by natural ventilation. ASHRAE Std. 62.1-2004 paragraph 5.1.1, Location and Size of Openings states that ""naturally ventilated spaces shall be within 25\' of operable wall or roof openings to the outdoors, the openable area of which is a minimum of 4% of the net occupiable floor area."" There is a louver in an overhead door in each of the workshops, plus one operable window. Because of the sandstorms in the area, the free unobstructed area through the opening of the louver does not meet the 4% requirement. Adding the area of the open window also does not meet that requirement. The area of the overhead door, when open however, more than meets the requirement. The standard mode of workshop operation in Dubai, where this project is located, is to leave the overhead doors open during normal working hours, except when there is a sandstorm. The other workshops in the area do not have roof ventilators, but rely strictly on the open overhead doors for ventilation. This project will have 2 wind-driven turbine roof exhaust fans located at the rear of each of the workshops on the far wall from the overhead door. Calculations show that, with an actual average wind speed in the area of 10.5 mph (the ASHRAE Fundamentals Handbook shows a max wind speed of 17 mph at 5%), the air change rate in the workshops will be from 6-9 air changes per hour, depending on the size of the workshop, i.e. the larger workshops will be closer to 6 and the smaller ones will be at 9. The exception in 62.1-2004 to paragraph 5.1 states that ""An engineered natural ventilation system when approved by the authority having jurisdiction need not meet the requirements of 5.1.1 and 5.1.2"". Paragraph 5.1.2 refers to control and accessibility of the operable openings, which this project meets. The authority having jurisdiction in Dubai will consider the calculations for the wind-driven turbine exhaust fans an engineered natural ventilation system. However, the likelihood of obtaining this approval in a timely fashion is questionable, as this project requires completion in less than 5 months; therefore we cannot wait for jurisdictional approval. As a result, we are writing this CIR and asking 2 questions: 1. Since the workshops have no interior walls and the roof exhausters are at the opposite end of the building, more than 25\' from the overhead doors, and are also approximately 25\' above the floor, will this be considered meeting the location of openings to the interior space? 2. Based on the different culture and customs of the country and the expectations of the workers relative to comfort conditions in naturally ventilated spaces, and based on these workshops having wind-driven exhaust fans providing 6-9 air changes per hour where other workshops have none, will this suffice for a natural ventilation system?" "1) Assuming that there is one operable overhead door in each of the workshops, that the open area of the door is at least 4% of the floor area, and that the entire workshop area is within 25 feet of the operable door, then the workshop space will meet the requirements of ASHRAE 62.1-2004 Section 5.1.1 or equivalent. For those workshops whose entire floor area is not within 25 feet of operable area, an engineered natural ventilation as mentioned in Exception to 5.1 would meet standard 62.1-2004, provided it is approved by the authority having jurisdiction. 2) The system described falls under the description of an ""engineered natural ventilation system"". Applicable Internationally, UAE." "None" "None" "X" "LEED Interpretation" "2129" "2008-06-27" "New Construction, Schools - New Construction, Commercial Interiors, Core and Shell, Existing Buildings" "This project is located on a multi-building medical campus in Illinois. Typical of a campus, it is composed of numerous existing buildings, parking structures, surface lots and circulation streets. The campus is proposing to build, as separately bid projects, a new inpatient building, some additions to existing buildings, and a new parking structure. Our intent is to pursue LEED Certification for the new inpatient building, a new multi-level parking structure and new portions of site work on the campus, but not the additions to existing buildings. One of the buildings included in the LEED project boundary is an open multi-level parking structure. The parking structure includes an enclosed combination stair/elevator lobby as part of the structure. The structure is classified as an unoccupied structure per ASHRAE 62.1-2004. A previous ruling on 9/18/2007 addressed the applicability of EQ credits to unoccupied spaces. The previous ruling is included for reference below: --- 9/18/2007 - Ruling The CIR is asking whether the requirements of EQ category of LEED applies to areas that are not occupiable (per ASHRAE Standard 62.1 2004 definition) or non-occupied (per LEED v2.2 EQc8 definition). The requirements of EQc1, EQc2, EQc6.1, EQc6.2, EQc7.1, EQc7.2, EQc8.1, and EQc8.2 are only applicable to occupiable or occupied areas; non-occupiable spaces that meet either the ASHRAE Standard 62.1 2004 or LEED v2.2 definition can be excluded from compliance with these credits. The requirements of EQp1, EQp2, EQc3.1, EQc3.2, EQc4.1,EQc4.2, EQc4.3, EQc4.4, and EQc5 do not differentiate between occupied (LEED definition) or occupiable areas (ASHRAE definition) and must be applied to all spaces within the building envelope. These credits and prerequisites affect adjacent spaces that might be occupiable and will also ensure that the construction team is not adversely affected by poor Indoor Environmental Quality --- ASHRAE 62.1 2004 defines occupiable as ""an enclosed space intended for human activities, excluding those spaces intended primarily for other purposes, such as storage rooms and equipment rooms, that are only occupied occasionally and for short periods of time."" Based on the precedent established by the above referenced CIR, we are requesting that the elevator lobby/stair and the parking structure be exempt from the need to comply with EQp1, EQc1, EQc2, EQc5, EQc6.1, EQc6.2, EQc7.1, EQc7.2, EQc8.1, and EQc8.2 since the structure is classified as unoccupied and the people will spend approximately one to two minutes in these spaces waiting for the elevators or walking up or down the stairs. We believe this meets the fundamental intent of both ASHRAE 62.1-2004, and the LEED EQ credits, because building users will occupy the elevator lobby and parking structure for very short periods of time, and therefore there will be no significant adverse occupant health impacts associated with not complying with these credits. The impacts to construction workers will also be insignificant, and there are no adjacent occupied spaces that could be adversely impacted by our proposed approach. Please confirm that the parking structure may remain within the LEED Project Boundary, and still remain exempt from compliance with the above referenced credits and EQp1." "The project team is asking whether a parking structure with an enclosed combination stair/elevator lobby can be assumed to be a non-occupied (per LEED v2.2 EQc8 definition) or non-occupiable space (per ASHRAE Standard 62.1 2004 definition), and therefore be exempted from the requirements of EQp1, EQc1, EQc2, EQc5, EQc6.1, EQc6.2, EQc7.1, EQc7.2, EQc8.1, and EQc8.2. The parking structure and its stair/elevator lobby are non-regularly occupied spaces and therefore still required to comply with EQp1, [if these credits are targeted] EQc1, EQc2, EQc5, and EQc7.1, and EQc7.2. Non-regularly occupied spaces are exempt from the requirements of EQc6.1, EQc6.2, EQc8.1, and EQc8.2. The project team should also acknowledge the parking structure and lobby as a vehicle garage and source of hazardous gases and pollutants. Accordingly, ASHRAE Standard 62.1-2004 has identified minimum exhaust and ventilation rates for garages and lobbies that should be followed to show compliance with EQp1. Applicable Internationally. " "None" "None" "X" "LEED Interpretation" "2150" "2008-06-09" "New Construction, Schools - New Construction, Commercial Interiors, Core and Shell, Existing Buildings" "The project is located in Downtown Los Angeles and is registered under LEED NC Version 2.2. It includes two high-rise towers with condominiums, affordable housing units, and apartments. It will pursue a LEED Silver rating. The LEED team is reviewing the requirements for EQ Prerequisite 1, Minimum IAQ Performance and compliance with ASHRAE 62.1-2004, including Appendix E. The team needs to assure that its design of the kitchen exhaust systems and venting of stove hoods complies with the ASHRAE standard, and we have reviewed the LEED Version 2.2 Credit Interpretation Rulings regarding this requirement: A recent USGBC CIR submitted on 8/30/07 regarding a 7-story residential unit im Massachusetts asked the following question: ""Under ASHRAE 62.1, 2004 are apartment kitchens required to be exhausted to the outdoors? If so, is there any way the bathroom exhausts could satisfy this requirement?"" On 9/24/07, the USGBC issued a ruling stating: ""The third question is asking whether under ASHRAE 62.1 2004, kitchens are required to be exhausted to the outdoors. If the kitchens qualify as naturally ventilated spaces, and there are no special requirements for combustion air or removal of combustion products, then there is no exhaust requirement. If the kitchens do not qualify as naturally ventilated spaces, then they will have to meet the exhaust requirements laid out in Appendix E: 100 cfm intermittent or 25 cfm continuous exhaust."" As noted above, the project includes two high rise residential towers, one being 47 stories and the other 28 stories in height. Due to the height of buildings and acoustical requirements of the City of Los Angeles pertaining to residences, the units are designed as mechanically ventilated spaces. Gas cook tops are provided in all residences, with recirculating exhaust hoods above each. To comply with ASHRAE 62.1, 2004 we propose extending a duct from the general exhaust riser system and terminating them with a grille in the ceiling or wall of each kitchen. We had analyzed air changes in the kitchen utilizing three different methods and as shown on the table below we have demonstrated that we meet ASHRAE ventilation rates. Is this an acceptable means of meeting the intent of the standard? Project T1 and T2 Residence space ventilation analysis ASRAE 62.1 - 2004 Bedroom is a Class 1 space Per Table 5-2 pg 9 Kitchen Air is Class 2 Per Table 5-2 pg 9 This air can be recirculated Per Section 5.17.3.2 But not to a Class 1 space Minimum Ventilation Rate Table 6-1 pg 12 CFM per person 5 CFM per square ft 0.06 cfm per sf Occupancy Density 10 per 1000 sf CFM per person 11 Minimum exhaust rate Table 6-4 pg 16 Kitchenettes 0.30 cfm per sf Appendix E Pg 38 Kitchen OSA = 100 cfm intermittant or 25 cfm continuous Tower 1 Tower 2 200 SF per person by Total SF: 767 683 People: 3.835 (say 4) 3.415 (say 4) 4 people x 5 = 20 cfm 20 cfm 767 sf x 0.06 = 46.02 cfm 40.98 cfm OSA cfm = 47 cfm 41 cfm by Occupancy rate 7.67 people 6.83 people at 11 cfm per person 84.37 cfm 75.13 cfm Kitchenette exh rate: Kitchen SF 67 70 at 0.30 cfm / sf 20.1 21 Design exhaust for: 100 cfm 100 cfm" "The proposed design approach appears to comply with the requirements of Standard 62.1. Yes, the kitchens may exhaust to a general exhaust riser instead of directly exhausting to outside, provided the ventilation rates as prescribed by the Appendix E, ASHRAE Standard 62.1-2004 are maintained. If the project team determines the requirements of Standard 62.1 to be ambiguous or unclear, the team should consider submitting a specific request for interpretation to ASHRAE. Applicable Internationally. " "1888, 1960, 1969, 2208, 5096, 5259, 5294" "None" "X" "LEED Interpretation" "2208" "2008-06-25" "New Construction, Schools - New Construction, Commercial Interiors, Core and Shell, Existing Buildings" "This CIR concerns ventilation design and IAQ performance of a six-story residential building in Nebraska. The unit floor plans will in part require use of mechanical ventilation to fully satisfy ASHRAE 62.1-2004 outdoor air requirements. It is clear the intent of ASHRAE Section 6 is establishment of minimum (mechanical) ventilation rates to enhance indoor air quality. We would like to verify our compliance path is acceptable for LEED certification. Question 1a: We intend to introduce the prescribed outdoor air requirements via 100% outside air type rooftop units. The rooftop units will provide filtered conditioned air for the commons areas and makeup air to the kitchen/toilet exhaust fans along with supplying outdoor ventilation air to the resident units through a ducted supply interconnected to the return air duct of each resident unit\'s condensing type gas-fired furnace. To ensure continuous supply of ventilation air, a whole building energy management control system (EMCS) shall verify that resident unit furnace fans are operating continuously. We believe this approach will ensure a consistent supply (ACH mechanical ventilation rates as prescribed by ASHREA 62.1) of clean (twice-filtered) outdoor air that will enhance indoor air quality. (Regional and local outdoor air quality is compliant.) Will this be an acceptable approach to achieve the required ventilation? Question 1b: To balance the impacts of ventilation rates on energy use, we propose to allow building residents limited access to the EMCS for the purpose of setting occupied/unoccupied schedules (see also provisions of ASHRAE Section 6.2.7). During unoccupied periods, the ventilation fans need not run continuously, thereby conserving energy otherwise consumed conditioning the outside air supply. Regular (ASHRAE prescribed) ventilation air changes would resume at the EMCS-set occupied periods. We believe this feature can preserve the intent of indoor air quality-ventilation for occupant comfort and well being, and be a valuable energy conservation measure. Will this control feature be acceptable to LEED as it relates to ventilation requirements and minimum IAQ performance? Question 2: Clarification of previous CIRs - Kitchens meeting natural ventilation as defined in ASHRAE 62.1-2004. CIR ruling dated 1/7/2008 stipulates ""direct exhaust is required to satisfy section 5.8."" Section 5.8 discusses combustion air and fuel-burning appliances. Please confirm CIR ruling dated 8/30/2007 (""If the kitchens qualify as naturally ventilated spaces, and there are no special requirements for combustion air or removal of combustion products, then there is no exhaust requirement."") is applicable in the circumstance of electric cooking ranges (thus no combustion air or combustion products). In short, some of our resident unit kitchens have operable windows satisfying Section 5.1 of ASHRAE and we will have electric cooking ranges. Under these conditions, the range hood is not required to be direct vented to the outdoors and a recirculating hood is acceptable? Question 3: We intend to install unvented natural gas fireplaces in the resident living units. These are allowed by our local code. Combustion air supply has been accounted for and will be provided. The fireplaces will be sized and installed in strict accordance with the manufacturer instructions for safe operation. Will use of unvented fireplaces be acceptable to LEED in terms of ventilation requirements and minimum IAQ performance?" "The project has submitted a multi-part inquiry for the interpretation of the ASHRAE 62.1-2004 requirements for a six-story residential building. This response is in order of the questions posed above. Response 1a: The approach outlined above meets the requirements of the credit. Response 1b: As per Table E-2, all living areas need a minimum of 0.35 ACH for the total conditioned area. As long as the total air volume delivered does not go below this rate, the project team may execute the control sequence as described. Response 2: Re-circulating hoods is acceptable for electric cooking ranges. Response 3: This question appears to be in direct contradiction to question 2 and does not comply with CIR ruling dated 8/30/2007 as well as section 5.8. Use of unvented fireplaces therefore does not meet the requirements of this pre-requisite." "1888, 1960, 1969, 2150, 5096, 5259, 5294" "None" "LEED Interpretation" "2303" "2008-09-23" "New Construction, Schools - New Construction, Commercial Interiors, Core and Shell, Existing Buildings" "Our project includes a large open industrial/distribution facility type space and will not have an HVAC system. Given the nature of the facility, we cannot provide 4% of the project\'s floor area as net operable area for natural ventilation. Therefore an engineered passive ventilation system is required to meet local code requirements. The project is located in an area with low scale development in a broad valley with no nearby hills or other obstructions. Under the current design, ventilation to the facility will be provided by roof mounted turbine ventilators to draw air out of the space coupled with low wall intakes for supply. The turbine ventilator is tested to draw a given CFM of air at a wind speed of 4 MPH. NOAA data indicates a minimum mean wind speed of 7 MPH in the area. We will calculate the ASHRAE 62.1 ventilation rate for the space based on the number of turbine ventilators installed and the CFM provided by each in a 4 MPH wind, knowing that the actual ventilation rate will be higher based on typical wind speeds. For example, one portion of the project is 45,000 SF. Based on ASHRAE 62.1, the required ventilation rate for a facility of this size will be 2,700 CFM ( 45,000 SF x 0.06 cfm/SF). The current design is based on a 24-inch throat size for the ventilation turbine. Based on the manufacturer\'s data this model will yield 2,350 CFM of exhaust at 4 MPH wind speeds. Due to local code requirements, this portion of the project will require 6 of these 24-inch turbines. The total volume of exhaust provided is 14,100 CFM. The design team would like clarification if this approach of using an engineered passive system to meet local code requirements also meets the requirements of IEQ prerequisite 1." "The project team is requesting clarification on whether an engineered natural ventilation system meets the requirements of EQp1. The Requirements of EQp1 in the LEED CSv 2.0 Reference Guide state that ""ASHRAE Standard 62.1-2004 Section 5.1 provides requirements on the location and size of ventilation openings for naturally ventilated buildings."" Exception to 5.1 in ASHRAE 62.1-2004 states, ""An engineered natural ventilation system when approved by the authority having jurisdiction need not meet the requirements of 5.1.1 and 5.1.2."" Therefore, if the project\'s engineered natural ventilation system is approved by the local authority, then the project will likely meet the requirements of EQp1. Final determination of credit achievement occurs during the review process. Applicable Internationally." "None" "None" "X" "LEED Interpretation" "2445" "2009-02-10" "New Construction, Existing Buildings, Commercial Interiors, Core and Shell, Schools - New Construction" "Our system currently relies on an engineered natural ventilation system to provide outside air to the apartment units, a design permitted by EQ-PR1 which states ""Naturally ventilated buildings shall comply with ASHRAE 62.1-2004, paragraph 5.1."" Although we do not meet the basic requirements of ASHRAE 62-2004, the standard incorporates an exemption allowing the ""authority having jurisdiction"" to approve engineered systems other than those explicitly described in the Standard. Our natural ventilation system has been designed in accordance with the City of St. Louis requirements, and as such is in compliance with paragraph 5.1 of 62.1-2004. Therefore, we believe our design meets the requirements of LEED EQ-PR1. Can this project satisfy IEQ prerequisite 1 through the use of an engineered natural ventilation system approved by the authority having jurisdiction?" "EQ Prerequisite 1, Minimum IAQ Performance, requires that naturally ventilated buildings comply with ASRHAE 62.1-2004, paragraph 5.1. The exception to paragraph 5.1 states that an engineered natural ventilation system approved by the authority having jurisdiction over the project does not have to meet the requirements of 5.1.1 and 5.1.2. The local jurisdiction approval is sufficient to meet the intent of this prerequisite. Applicable Internationally." "5193" "None" "X" "LEED Interpretation" "2539" "2009-06-04" "New Construction, Schools - New Construction, Commercial Interiors, Core and Shell, Existing Buildings" "Our project team would like to clarify if the design of our building meets the natural ventilation requirement of ASHRAE Standard 62.1-2004. The project is a large factory building with the majority of the space not mechanically ventilated. The naturally ventilated space is 64,700 sq meters of floor space. The highest point in this space is the peak of the roof and it is at least 9.7 meters from floor to the bottom of the beams. There is a row of single story offices which are mechanically ventilated in the middle of this space but the area above and around the offices does not block or divide the ventilated space with any full height walls. The walls around the perimeter of the naturally ventilated space have operable louvers and the roof has large area of central roof ridge vents. The total opening area of the louvers and the roof vents is 5,673 sq meters, which is 8.8% of the net occupiable floor area. The ventilated space is a contiguous space and all of the openings are on the roof and walls, but some indoor space is not within 25 feet of any opening. The natural ventilation design of wall louvers and roof vent has got the approval from ""Local Zoning Authorities"" and ""Occupational Safety and Hygiene Management Department"" Does this constitute naturally ventilated space which complies with the requirement of ASHRAE 62.1?" "The applicant is asking if the project\'s natural ventilation design which has been approved by ""Local Zoning Authorities"" meets the requirements of ASHRAE 62.1 or equivalent. Per a previous CIR dated 12/11/2008, there is an exception to paragraph 5.1 of ASHRAE 62 that states that an engineered natural ventilation system approved by the authority having jurisdiction (AHJ) over the project does not have to meet the requirements of 5.1.1 and 5.1.2. Approval by the AHJ is sufficient to meet the intent of this prerequisite provided the AHJ approval indicates that the engineered system is sufficient to meet the intent of ASHRAE 62.1, as opposed to local code requirements. Applicable Internationally." "5193" "None" "X" "LEED Interpretation" "2636" "2009-06-30" "New Construction, Schools - New Construction, Commercial Interiors, Core and Shell, Existing Buildings" "We are designing a 4,000 square foot visitor\'s center for a state park which has 3 full-time staff and an average of approximately 80 visitors per day who spend anywhere from 5 minutes to 1 hour in the building. The building ventilation system is designed for natural ventilation using operable windows and doors. The design complies with the LEED NCv2.2 requirements for location and size of window openings in accordance with ASHRAE Standard 62.1-2004, Section 5.1 and with the International Mechanical Code for naturally ventilated spaces. It includes residential-type air to air heat pumps which condition and supply recirculated air from within the building. There are no supply ducts bringing in outside air, similar to a residential design. Infiltration provides the minimum outside air flow. Exhaust fans have been provided in the bathrooms and in the janitor\'s closet as required by the International Mechanical Code. ASHRAE 62.1 - 2004, section 6.2.8 indicates that ""exhaust make-up air may be any combination of outdoor air, recirculation air, or transfer air."" The make-up air for the exhaust fans is designed to be by infiltration. It is pulled from the neighboring spaces via a duct (transfer air), which creates negative pressure in those spaces, which causes infiltration (outdoor air). Again, similar to residential design. A EQp1 CIR dated 5/15/2007 regarding a similar situation implied that air transfer through a space meeting all the requirements of natural ventilation did not make that space a ""mixed-mode"" ventilated space. Therefore, we believe the project should be considered naturally ventilated, and does not have to meet the mechanical requirements of ASHRAE 62.1-2004, Sections 4 through 7. We propose that spaces that are naturally ventilated and have air transferred to exhausted spaces cannot be classified as ""mixed-mode."" We do not believe that it is the intent of LEED that bathrooms (or other spaces that require mechanical exhaust) have completely independent ventilation and conditioning systems, as this would increase the carbon footprint by requiring additional equipment and added energy costs. Please advise whether you agree that classifying the spaces adjoining the restrooms and the janitors closet as naturally ventilated (even though air is being transferred through for make-up air) is accurate and aligns with all applicable criteria. If not, please explain your reasoning using the applicable standards and describe the design changes necessary to meet the criteria." "Naturally ventilated spaces can be used for make-up air to mechanically exhausted spaces such as toilet rooms; a mechanical outdoor air supply system is not required. Note that Standard 62.1-2007 does not define or use the term ""mixed mode"" so this classification is not relevant to the application of the Standard. Naturally ventilated spaces meeting the requirements of Section 5.1 do not have to comply with Section 6, but all other application sections of Chapters 4, 5, and 7 still apply.Applicable Internationally." "None" "None" "X" "LEED Interpretation" "5053" "2007-05-15" "New Construction, Schools - New Construction, Commercial Interiors, Core and Shell, Existing Buildings" "The project involves the remodeling of a fieldhouse building in Toledo, OH, to incorporate classrooms, lecture halls and academic office spaces. The Mechanical Systems will be completely replaced to accommodate an entirely different space use. The Project Team would like to use the IAQ Procedure, as described in Section 6.3 ASHRAE Standard 62.1-2004 (the ""Standard""), in place of the Ventilation Rate Procedure of the same Standard. Rather than determining the volume of outside air needed based on space type/application, occupancy level, and floor area, the building and ventilation systems are designed to maintain the concentrations of specific contaminants at or below certain limits identified during building design and to achieve the design target level of perceived indoor air quality acceptability by building occupants and/or visitors, excluding dissatisfaction related to thermal comfort, noise and vibration, lighting, and psychological stressors. The design will strive to provide satisfaction in those areas as well, but those areas will not be measured by this procedure. The Project Team will use the documentation guidelines prescribed in Section 6.3.2 of the Standard with all assumptions documented according to Sections 4.3, 5.2.3, 5.17.4 and 6.3.2. The Project Team will use mass balance analysis as their design approach, using a computer-generated model to simulate contaminant levels, ventilation rates and effectiveness of mechanical filtration systems. The goal of the Project Team, by using this procedure to guide their HVAC design, is to optimize energy performance without compromising indoor air quality." "The CIR is inquiring if the IAQ Procedure, as described in Section 6.3 ASHRAE Standard 62.1-2004, can be used in place of the Ventilation Rate Procedure of the same Standard to document compliance with the requirements of this prerequisite. The Ventilation Rate Procedure methodology found in Section 6.2 of ASHRAE 62.1-2004 is the required approach in EQp1, since it is prescriptive and therefore more straightforward to apply. The Ventilation Rate Procedure is based on contaminant sources and source strengths that are typical for common space types listed in the Standard. The Indoor Air Quality (IAQ) Procedure methodology found in Section 6.3 of ASHRAE 62.1-2004 and proposed by this project team is performance-based and relies on identification of contaminants of concern, sources for those contaminants, concentration targets, and perceived acceptability targets. The project-specific nature of the IAQ procedure methodology makes it less commonly used and more difficult for USGBC to evaluate. Therefore USGBC cannot allow its use to show compliance with LEED NC v2.2 EQp1. Please note that the intent behind this prerequisite is to encourage designers to take the most stringent and conservative prescriptive approach to providing fresh air. The language of the prerequisite asks designers to compare the rates recommended under Ventilation Rate Procedure with that required by their local code and to pick the most stringent. As for the project team\'s legitimate concern with energy efficiency, the ""additive"" Ventilation Rate Procedure adopted in the ASHRAE Standard 62.1-2004 reflects concerns for energy consumption with elevated ventilation rates. The recommended rate under the Ventilation Rate Procedure in ASHRAE Standard 62.1-2004, in many important occupancy types and projects can result in lower ventilation rates than those required by the earlier version of the Standard - Standard 62.1-2001. Applicable Internationally. " "None" "None" "X" "LEED Interpretation" "5096" "2008-01-07" "New Construction, Schools - New Construction, Commercial Interiors, Core and Shell, Existing Buildings" "This CIR is in reference to ventilation design for a four-story, 238-unit residential building in Massachusetts. The building in question has approximately 30 distinct unit types-from studios to three-bedroom units. The focus of this CIR is on the LEED requirements for ventilation within the residential units. The proposed ventilation of the building uses a combination of mechanical and natural ventilation as described per the following: The total building conditioned area of the building is 263,256 square feet. Approximately 10 percent of the building area is common space; this public space is mechanically ventilated per the requirements of ASHRAE 62.1-2004. Public hallways are supplied with 100% outdoor air from constant volume roof top air handlers. Other common areas including Library, Exercise Room, Community Room, and Leasing Office spaces have individual air handling units. The Exercise Room, Community Room, and Leasing Office have outdoor air supply. The Library is naturally ventilated with all spaces less than 8 meters from operable windows. The outdoor air to the public spaces is filtered, heated and cooled as required to maintain the temperature at a preset level. The living units are comprised of various combinations of the following spaces: Kitchens, Unit Entryways, Unit Corridors, Dining Areas, Living Rooms, Dens, Bedrooms, Closets, Mechanical Rooms, and Bathrooms. Heating and cooling for the units is provided by a recirculating fan coil unit. Every unit Kitchen is equipped with an occupant-controlled (intermittent) 100 cubic feet per minute exhaust hood and every unit Bathroom has an occupant-controlled (intermittent) 60 cubic feet per minute exhaust fan; both of these are ducted directly to the exterior. Based on the EQ prerequisite 1 CIRs (Rulings dated 5/15/2007 and 9/24/2007) the ""calculations to demonstrate compliance with ASHRAE Standard 62.1-2004 for mechanically ventilated spaces in residential projects, will include showing air changes per hour and/or cfm per person outdoor air ventilation rates (for living areas), and cfm exhaust (for bathrooms and kitchens), according to the requirements of Appendix E."" As per the requirements of ASHRAE 62.1-2004, Appendix E, Table E-2, the ""living areas"" volume is defined as all area within the conditioned space. Many of the residential units utilize an open plan that joins Living Room, Dining Area, Kitchen, Unit Corridor, and Unit Entryway into a single conditioned volume. In some instances a small portion of the living area volume is greater than the 8 meter distance from window wall to be considered naturally ventilated; this area is associated with the functions of Kitchen, Unit Entryway and Corridor use. Question 1a: As per ASHRAE 62.1-2004, Appendix E, Table E-2, Outdoor Air Requirements for Ventilation of Residential Facilities, Footnote C; the ventilation requirements for Kitchens and Bathrooms may utilize supply air from adjacent living areas to compensate for exhaust air. Please confirm that no direct outdoor air supply is required for Kitchens and Bathrooms. Question 1b: For living units with the Kitchen entirely within the 8 meter distance from window wall-and meeting the requirements of natural ventilation as defined in ASHRAE 62.1-2004-is a kitchen exhaust required? Question 2a: What, if any, outdoor air supply is required for Unit Entryways and Unit Corridors? Can the entry and corridor spaces be excluded from being considered ""occupiable spaces"" since there are not large enough to be furnished with desks, chairs, etc. and are only occupied for short periods of time? Question 2b: If outdoor ventilation air is required to the Unit Entryway, but not the Kitchen-in instances where the Unit Entryway and Kitchen are greater than 8 meters from the window wall and the Unit Entryway is substantially open to the Kitchen-can we consider the Unit Entryway to be a part of the Kitchen and thus the requirements of ASHRAE 62.1-2004 are met through the inclusion of the required exhaust fan? Question 2c: If the option described in Question 2b is not acceptable, then is mechanical ventilation required for the Unit Entryway? If so, what is the calculation method for this outdoor air supply? Can we deduct the volume that is within 8 meters of the window wall as naturally ventilated area and only provide ventilation air for the remainder of the Unit Entryway volume that is beyond 8 meters? Question 2d: Based on the acceptable ventilation calculation method defined in the response to Question 2c, can the ventilation air be transferred from the positively pressurized public hallway that receives 100 percent outdoor air? Question 3: For residential units with Dens, internal rooms designated for home office use, mechanical ventilation will be provided per the requirements of ASHRAE 62.1-2004. The outdoor air in these spaces is ducted directly to the Dens from the same equipment that supplies the public hallway air distribution system. Please confirm that this is acceptable. Question 4: For every unit type that has a Bedroom, the entire floor area of these rooms is within 25 feet of a window wall with an operable window opening dimension greater than 4 percent of the floor area of the spaces it serves. Based on these data we believe that these rooms are in compliance with the LEED requirements for natural ventilation, please confirm. Question 5: Where mechanical ventilation is required for outdoor air supply, will the following system be in compliance? Adding an appropriately sized fresh air intake supply to the current re-circulating fan coil unit where the fan coil unit is designed to be resident-controlled, using a thermostat that includes settings for (1) automatic operation based on actual temperature in the space versus the resident-controlled set point, In ""automatic mode"" the fan will start as soon as the thermostat calls for cooling or heating. Since the fan operation will be intermittent, outside air supply to the unit will also be intermittent. (2) fan-only operation In ""fan only mode"" outside air supply and re-circulation will be continuous. Hot water coils or DX system will be activated only when the thermostat detects that space temperature drop below or rises above the thermostat setting. (3) an off-position. In addition, a resident controlled damper on the outdoor air intake will be provided. This damper is provided to allow for occupant control over potential drafts from outside air intake, to control over additional utility cost associated conditioning outdoor air, and to prevent the coil from freezing when the system is in the off position as outside air penetrates the system. Question 6: The ASHRAE 62.1-2004 standard does not seem to address outdoor air ventilation supply requirements for public stair towers (including egress stairs). Please confirm that there are no supply air requirements for stairs as per LEED EQ prerequisite 1." "The applicant submitted a multi-question CIR requesting clarification on a number of items that relate to EQ Prerequisite 1, Minimum IAQ Performance, and ASHRAE Standard 62.1-2004. Please note that the intent of a CIR is to provide clarifications about the LEED" "1888, 1960, 1969, 2150, 2208, 5259, 5294" "None" "LEED Interpretation" "5112" "2008-02-04" "New Construction, Schools - New Construction, Commercial Interiors, Core and Shell, Existing Buildings" "The UCS suite is located on the 8th floor of a 12 story building in downtown Washington, DC. The building was built in the 1960\'s. This suite covers the entire floor of the building. The types of spaces in the suite consist of offices, open offices, conference room, meeting rooms, lunch room, pantry, lan room, storage and copy rooms. There are four meeting rooms and a conference room (room 876) in this suite. The meeting rooms are located along the perimeter of the suite and are being served by a separate exterior zone 100% outside air system. The conference room is located in the interior and is served by air-handlers in the penthouse which provide 25% outside air to the interior zones. These air-handlers serve other floors in the building also. This conference room is a critical space and currently does not meet the ASHRAE 62.1-2004 standard. The total outside air being provided to the suite is 6313 CFM. The total occupancy for the suite will be 85 people. Thus, we are supplying 74 CFM per person for the entire suite. For each space, the amount of outside air that we are providing is over 30% above the ASHRAE 62.1-2004 standard, except the conference room. Per ASHRAE 62.1-2004, we are 36% below the amount of ventilation air that is required for the conference room. This conference room is existing, with an area of 480 SF and occupancy of 24 people. 600 CFM of supply air was provided to this space under the existing design. Since the room did not change under the new design, the quantity of air was kept the same. The space will not be used for more than two to three hours at a time. Per local codes we are allowed to use a transfer fan and provide the extra air from adjacent office space to meet the ventilation requirements. We have the following questions: 1) Given the high amount of outside air for the rest of the suite, does USGBC accept the supply air quantity for the conference room for the minimum IAQ performance pre-requisite and increased ventilation credit? 2) If we need to increase the supply air quantity, how much do we need to increase it by, given that main air-handler provides 25% OA? 3) Does USGBC allow the use of a transfer fan to provide additional supply air to the space? 4) Are there other options that the owner can consider to achieve the increased ventilation credit?" "The CIR is requesting guidance on the exemption of or treatment of a conference room space in regards to the minimum ventilation requirements of EQ Pr1, and the requirements of EQ Cr2. All occupiable spaces are required to meet the minimum ventilation rates to satisfy this prerequisite, including the conference room. From our review of the information presented, it appears that the project team has misunderstood the application of the ASHRAE 62.1-2004 Ventilation rate procedure calculations. Please recheck your ventilation calculations, and if necessary, consult the ASHRAE 62.1 User\'s Manual for more information. As a result, the answers to your questions are as follows: 1) All occupiable spaces are required to meet ASHRAE 62.1-2004 to meet EQPr1. All spaces are required to show a breathing zone ventilation rate at least 30% above ASHRAE 62.1-2004 to achieve EQ Cr2. The submitted information is not sufficient to show compliance with either of these requirements. 2) This is a design question for the project team and not related to credit interpretation. Your ASHRAE 62.1 calculation should indicate this number. 3) Use of a transfer fan is an acceptable means of complying with the ventilation rate requirements, assuming that both spaces are re-calculated such that the same quantity of air is not double-counted. That data must be properly accounted for using Appendix A in ASHRAE Standard 62.1. 4) EQ C2 allows an alternate approach for naturally ventilated spaces. In addition there are many ways in which the ventilation system might be adjusted or modified to meet the credit requirements. This is a design question for the project team and not related to credit interpretation. Applicable Internationally. " "None" "None" "X" "LEED Interpretation" "5193" "2009-03-11" "New Construction, Schools - New Construction, Commercial Interiors, Core and Shell, Existing Buildings" "Our project is a multi-story residential building in New York City. The residential units all comply with the New York City Building Code (NYC Code) as naturally ventilated. Bathrooms require 50 CFM continuous exhaust, and therefore exceed ASHRAE 62.1-2004 requirements. The ventilation design is described below: >NATURALLY VENTILATED AREAS: NYC Code requires operable roof or wall openings with a minimum openable area of 5% of the net occupiable floor area, a 25 % increase above ASHRAE 62.1-2004. Kitchens, defined as greater than 80 SF by NYC Code, must be naturally ventilated and therefore all have access to operable openings. Kitchenettes, defined as less than 80 SF by NYC Code, can provide continuous exhaust ventilation at 2 CFM/SF in lieu of natural ventilation. However, NYC Code does not restrict naturally ventilated areas to within 8m (25 FT) from operable openings and therefore several of the units contain small areas (between 50-200 SF) beyond 8 m (25 FT). By law every unit exceeds the ASHRAE-required ratio of operable openings to occupiable floor area by a minimum of 25%, and in application often far exceed the legal requirement. QUESTION 1: Since the entire residential unit is approved as naturally ventilated ""by the authority having jurisdiction"" can the entire residential unit considered naturally ventilated for this prerequisite and is therefore exempt from the 8 m (25 FT) limit imposed by ASHRAE 62.1 2004 Section 5.1.1 consistent with the ""Exception to 5.1"" regarding ""engineered systems"" and LEED-NC CIR ruling from 1/13/2009? QUESTION 2: If not exempt, can the project comply with EQp1 under the approach for ""engineered natural ventilation system"" by mechanically inducing more than 0.35 ACH in all occupiable areas located more than 8m (25 FT) from operable openings? The engineered system will include: > A minimum 25% increase above ASHRAE 62.1-2004 in fresh air provided through operable openings (as described above). > Continuous bathroom exhaust fans, continuous exhaust at all kitchenettes without natural ventilation, and continuous dryer exhaust with variable speed CFM (based on building-wide pressure sensor readings). Makeup air to the exhausted areas is provided by adjacent naturally ventilated spaces via infiltration and natural ventilation, per the assumptions of Table E-2. > The total exhaust CFM provided for each residential unit is more than 15 CFM per occupant and is also substantially more than 0.35 air changes per hour (ACH) for areas greater than 8 m (25 FT) as required in Table E-2 for residential living areas. > All occupiable spaces greater than 8m (25 FT) of operable openings would a) be located between the operable openings and exhaust fans, or b) have transfer grills connecting the spaces to the room containing the exhaust fan to induce airflow. In no case does the area greater than 25 FT from operable openings require more than 10 CFM to induce 0.35 ACH." "The project team is requesting clarification for demonstrating compliance with this prerequisite. For Question 1, local codes may be used to demonstrate compliance, provided that documentation is submitted to validate that all sections of the local code are equal to or more stringent than ASHRAE 62.1-2004. In this particular case, the local code is not as stringent as ASHRAE 62.1-2004 and therefore does not meet the requirement. The alternative approach presented in Question 2 appears reasonable. However, in order to demonstrate compliance, a detailed narrative and support documentation must be provided for the LEED submission, to adequately justify the alternative compliance path proposed. Applicable Internationally. " "2445, 2539" "None" "X" "LEED Interpretation" "5259" "2007-05-15" "New Construction, Schools - New Construction, Commercial Interiors, Core and Shell, Existing Buildings" "Background 1: We are designing a mixed use hotel / apartment building in the Philadelphia area. We are investigating the ventilation strategy required to comply with LEED EQ p1 for the living areas in hotel / apartment units. We understand that the IMC 2003 is the applicable mechanical code. We are proposing the following ventilation strategy: natural ventilation through operable windows for hotel / apartment living areas and bedrooms with recirculating systems (PTAC units) for space conditioning; mechanical ventilation via exhaust fans and transfer air for bathrooms and kitchens in hotel / apartment units (see question 2); and central mechanical ventilating units serving corridor / core areas. Question 1: Under this strategy we believe that the living areas and bedrooms would qualify as ""natural ventilation"" not ""mixed mode ventilation"" since the PTAC units are recirculating only and do not draw any outside air. Both the International Mechanical Code and ASHRAE 61.1-2004 allow recirculation-only mechanical systems to be installed in spaces where ventilation is provided by natural means. Since the living areas will comply with the natural ventilation requirements, they would not require the mechanical introduction of outside air as is necessary for ""mixed mode ventilation."" The corridor / core areas would be classified as ""mechanically ventilated."" We would like verification that including PTAC units in a space with operable windows does not change its classification from ""naturally ventilated"" to ""mixed mode."" Background 2: ASHRAE 62.1-2004, Appendix E, indicates that ventilation in residential living areas ""is normally satisfied by infiltration and natural ventilation."" It also indicates that ""the air exhausted from kitchens, baths, and toilet rooms may utilize air supplied through adjacent living areas to compensate for the air exhausted."" Section 6.2.8 indicates that ""exhaust makeup air may be any combination of supply air, recirculated air, or transfer air."" Question 2: We are proposing that the makeup air for kitchen and bathroom exhaust be drawn from corridor ventilation by undercutting the doors to hotel / apartment units. The air would be transferred from the corridor through the living areas to the toilet and kitchen areas. In this scenario, we believe the living / bedroom areas would comply with natural ventilation requirements and be considered ""naturally ventilated"" while the corridors / kitchens / bathrooms would comply with mechanical ventilation requirements and be considered ""mechanically ventilated."" We wouldn\'t have any spaces that are considered ""mixed mode ventilation."" Is this classification accurate based on LEED guidelines? We would like verification that transferring air through a space with operable windows does not change its classification from ""naturally ventilated"" to ""mixed mode."" Background 3: ASHRAE 62.1-2004, Appendix E, indicates that ventilation in residential living areas ""is normally satisfied by infiltration and natural ventilation."" It also indicates that ""the air exhausted from kitchens, baths, and toilet rooms may utilize air supplied through adjacent living areas to compensate for the air exhausted."" Section 6.2.8 indicates that ""exhaust makeup air may be any combination of outdoor air, recirculated air, or transfer air."" Question 3: It appears that the applicable code (IMC 2003) and ASHRAE 62.1-2004 Appendix E and section 6.2.8 allow makeup air for toilet and kitchen exhaust to come from infiltration (""outdoor air""). Is this acceptable under LEED EQ p1?" "The CIR has posed three follow on questions regarding residential compliance under the referenced ASHRAE standard. The first question asks if living spaces served by operable windows and recirculation only air conditioning units qualify as ""naturally ventilated"" under the referenced standard. If the living areas and bedroom spaces meet the requirements for location and size of openings for naturally ventilated spaces, outlined under section 5.1.1 of ASHRAE 62.1-2004, these spaces are considered naturally ventilated. The second question is asking whether naturally ventilated spaces with air transfer to mechanically ventilated spaces are considered mixed mode. These space will be considered natural ventilated, if they meet the criteria outlined in section 5.1 of ASHRAE 62.1-2004. While this approach may meet the credit intent, the design team should consider negative factors such as noise transfer and fire ratings. The best overall design approach will take into account these factors as well as climate and local codes for the sake of the building occupants. The third question is asking if infiltration as a source of makeup air for toilet and kitchen exhaust, acceptable under ASHRAE 62.1-2004 Appendix E, is acceptable under the requirements of EQp1. The EQp1 language asks project teams to choose the more stringent requirements of the local applicable code and ASHRAE 62.1-2004 Ventilation Rate Procedure. If ASHRAE 62.1-2004 Ventilation Rate Procedure is the more stringent of the two, then the project team can refer to Appendix E for Residential Facilities and Healthcare facilities. Appendix E is referred to in Note 6 of General Notes for Table 6-1, under section 6.2 Ventilation Rate Procedure in ASHRAE 61.1-2004 and allows projects to use air supplied through adjacent living areas to compensate for the air exhausted." "1888, 1960, 1969, 2150, 2208, 5096, 5294" "None" "LEED Interpretation" "5294" "2008-02-11" "New Construction, Schools - New Construction, Commercial Interiors, Core and Shell, Existing Buildings" "This project involves the construction of a new 800,000 square foot events center in Orlando, Florida. This facility will be a sports and entertainment arena for all of Central Florida to enjoy. It will be capable of hosting events of local, regional, and national importance, such as concerts and family shows, civic and community-based events, and professional and amateur sporting events, including but not limited to NCAA and state competitions and NBA and AFL games. The seating bowl portion of this facility will be designed to accommodate approximately 19,000 spectators. The Prerequisite for EQ Pr 1 requires designing mechanical ventilation systems to meet ASHRAE Standard 62-2004 using the Ventilation Rate Procedure. According to this method of the Standard, the prescriptive outside air rate for a sports arena would be 7.5 cfm per person plus 0.06 CFM per square foot, for approximately 152,000 cfm for this facility. The ASHRAE Standard also has an alternate compliance path called the Indoor Air Quality (IAQ) Procedure. The IAQ Procedure is performance-based and requires a more detailed analysis of the space, including identification of contaminants of concern, sources for those contaminants, concentration targets, and perceived acceptability targets. Using the IAQ Procedure, it is estimated that the ventilation rate could be reduced to approximately 95,000 cfm. This would be accomplished using gas phase filtration similar to Bioclimatic bio-polar ionization filters in conjunction with MERV 13 particulate filters. A life cycle cost analysis will be performed to confirm that the increased cost of filtration will be offset by the energy savings from reducing outdoor air quantities, especially in a hot and humid climate like Orlando. The Project Team would like to use the IAQ Procedure for this project, as described in Section 6.3 ASHRAE Standard 62.1-2004 (the ""Standard""), to be able to provide the best Indoor Air Quality while consuming the least energy over the life of this facility. The Engineering firm responsible for designing the HVAC systems has extensive experience with sporting venues, and it is their experience that the IAQ Procedure is often the best choice for venues with large occupancies such as this facility. In many cases, using the IAQ Procedure can offer significant cost savings in equipment and energy, while maintaining proper ventilation and indoor air quality. The design team feels that using either the IAQ Procedure or Ventilation Rate Procedure as allowed by ASHRAE meets the intent of the LEED Prerequisite." "The CIR is enquiring as to whether the ASHRAE 62.1-2004 IAQ Procedure can be used in lieu of the Ventilation Rate Procedure for the purposes of EQp1. A LEED-NC v2.2 EQp1 CIR ruling dated 5/15/2007 has already addressed this issue, and does not allow for this alternate compliance path. The rationale behind that ruling still stands. Applicable Internationally. " "1888, 1960, 1969, 2150, 2208, 5096, 5259" "None" "X"