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" "5061" "2007-08-13" "New Construction, Core and Shell, Schools - New Construction, Commercial Interiors, Existing Buildings" "The project intends to meet the permanent entryway system and exhaust system requirements of the credit criteria. The project is requesting an interpretation of the acceptability of the method proposed to meet the MERV 13 filtration requirement. The project HVAC system is a dual path HVAC system: Outside air for ventilation is provided by 100% fresh air air-handlers with heat recovery from exhaust air. These air handlers will be equipped with MERV 13 filtration or better as well as other features for achieving high efficiency. Zone conditioning will be provided by fan coils receiving a mixture of return air from the space and fresh air from the air handlers described above. In this respect, the fan coils provide a similar function to that of fan powered terminal units on a conventional variable air volume system and similar to that system, MERV 13 filtration is not possible on the zone fan coil level. The design team believes that the design meets the intent of the credit for filtration since all outside air introduced into the building will be filtered to the high standard of MERV 13." "The CIR inquiry indicates that the project receives 100% of its outside air through air handling units that are equipped with MERV 13 filtration, as required by EQc5. Additional fan coil units are located within the building to provide supplemental zone conditioning. The fan coil units supply a combination of the minimum ventilation outdoor air plus air recirculated from the room. Since the fan coil units recirculate room air, they must have MERV 13 filters, which are available on the market. Therefore, the design, as described, does not appear to meet the intent of the credit. \n\n **Updated January 1, 2014\n NOTE: UPDATED CREDIT LANGUAGE FOR 2009 STATES THAT ""PARTICLE FILTERS OF AIR CLEANING DEVICES SHALL BE PROVIDED TO CLEAN THE OUTDOOR AIR AT ANY LOCATION PRIOR TO ITS INTRODUCTION TO OCCUPIED SPACES"". REQUIREMENT FOR FILTRATION ON RETURN AIR IS NO LONGER APPLICABLE TO ANY VERSION OR ANY RATING SYSTEM." "None" "None" "LEED Interpretation" "5064" "2007-08-13" "New Construction, Existing Buildings, Commercial Interiors, Core and Shell, Schools - New Construction" "Our LEED-NC v2.2 project includes 5 high rise hotels having an approximate total of 5,000 guest rooms with two-pipe chilled water fan coil units and supplemental electric heating. The windows within the guest rooms are not operable, and mechanical ventilation is ducted directly to each guest room from central air handling systems utilizing 100% outdoor air commercial rooftop units. The amount of outdoor air delivered to each guest room meets or exceeds the requirements of ASHRAE 62.1-2004. All air exhausted from the toilet rooms is ducted directly to the outdoors. The third part of the requirement for EQ 5 requires MERV 13 or better filtration on all building HVAC systems serving regularly occupied spaces. The guest room fan coil units cannot physically handle the MERV 13 filters due to filter size and increased air pressure drop across the filter. The corridor supply units, which are commercial grade, can and will be provided with MERV 13 filters. The project design will also meet both of the other requirements for this credit for the entryway systems and chemical and pollutant exhaust and control. We propose to meet the credit requirements by providing MERV 8 filters on all guest room fan coil units and MERV 13 filters on the commercial rooftops serving the corridors. All outdoor air ventilation is provided through the rooftop units. The fan coils will handle only recirculated air within each guest room. These filtration levels are the best that the systems can accommodate. We feel that this approach meets the intent of the credit while providing a practical and superior approach to hotel applications. Is this approach acceptable?" "The filtration portion of NCv2.2 EQc5 requires MERV 13 filters should be applied to process both outside air and return air that is to be delivered as supply air. The recirculated air that you are referencing would be considered return air, and would therefore need to be filtered with MERV 13 filters. The credit states that the design team should ""Ensure that air handling units can accommodate required filter sizes and pressure drops"". The fan-coil units would be considered to be air handling units as they process air for human use. MERV 13 filters are available in a 2"" thick version. Upsizing of fan coil fan motors would allow for the increased pressure drop required for the filter. NOTE: UPDATED CREDIT LANGUAGE FOR 2009 STATES THAT ""PARTICLE FILTERS OF AIR CLEANING DEVICES SHALL BE PROVIDED TO CLEAN THE OUTDOOR AIR AT ANY LOCATION PRIOR TO ITS INTRODUCTION TO OCCUPIED SPACES"". REQUIREMENT FOR FILTRATION ON RETURN AIR IS NO LONGER APPLICABLE TO ANY RATING SYSTEM. Applicable Internationally. " "None" "None" "X" "LEED Interpretation" "5225" "2009-05-20" "New Construction, Existing Buildings, Commercial Interiors, Core and Shell, Schools - New Construction" "This CIR references the provisions for appropriate air filtration media for an office and warehouse distribution facility, as per EQc5. The intent of this credit is to minimize exposure of occupants to potentially hazardous particulates and chemical pollutants. We have accomplished this by traditional means in the office areas by: 1. Employing permanent entryway systems, 2. Exhausting areas with hazardous gases or chemicals sufficiently, 3. Providing proper filtration media: a. The main and warehouse offices will have MERV-8 pre-filters and MERV-13 final filters. b. Green cleaning strategies have been employed throughout the building. As stated on the USGBC website, ""LEED for New Construction and Major Renovations is a green building rating system that was designed to guide and distinguish high-performance commercial and institutional projects, with a focus on office buildings. Recognizing that the warehouse is a ""LEED challenged building type"" and clearly and systematically differentiates from commercial office buildings, there have not been any specific requirements developed to consider this building type. Therefore, to design for minimizing exposure of occupants to potentially hazardous particulates and chemical pollutants in this building type, we referenced ASHRAE Standard 52.2-1999 that provides specifics to warehouse efficiency requirements. The following recommendations were implemented: 1. Selecting the highest recommended filter efficiency for warehouses (MERV-8) based on ASHRAE Standard 52.2-1999. a. ASHRAE recommends 10% (MERV-1) to 35% composite average particle size efficiency for warehouses (MERV-8). b. Typical applications for MERV-13 filtration according to ASHRAE are for high end Commercial Office buildings and healthcare areas such as surgical suites/operating rooms. Based on following ASHRAE\'s requirements, MERV-8 filtration (35%) is considered high end for warehouses. 2. Green cleaning strategies will be employed throughout the building. 3. Trucks are not permitted to idle. 4. No propane fork trucks are permitted or combustion vehicles in the interior. Although we have been awarded this credit for several of our projects using MERV-8 filters in warehouse buildings we wanted to clarify it for other design teams." "The applicant is asking if the warehouse spaces of the project can be exempted from the MERV-13 filtration requirement of this credit. No, based on previous LEED NC 2.2 CIRs, dated 8/13/2008 and 2/12/2008, all air (ventilation and return air) supplied to occupied areas of the building must pass through MERV-13 filtration and therefore the warehouse areas cannot be exempt from this credit requirement. Applicable Internationally. " "None" "None" "X"