TheLEED for Homes Rating System (v4)requires blower door testing in theEnergy and Atmosphere (EA) Credit: Air Infiltrationto measure envelope leakage, expressed as air changes per hour (ACH) at a specific pressure differential.
According to theLEED Reference Guide for Homes Design and Construction (v4):
EA Credit: Air Infiltration (1–3 points)
Conduct a blower door test to measure envelope leakage in air changes per hour (ACH) at a pressure differential of 50 pascals (Pa). This standardizes the measurement of air tightness across projects.
Source: LEED Reference Guide for Homes Design and Construction, v4, Energy and Atmosphere Credit: Air Infiltration, p. 124.
TheLEED v4.1 Residential BD+Crating system confirms:
EA Credit: Air Infiltration
Envelope leakage is measured using a blower door test at 50 pascals, reported as ACH50, to assess the airtightness of the building envelope.
Source: LEED v4.1 Residential BD+C, Credit Library, accessed via USGBC LEED Online.
The correct answer is50 pascals(Option B), as this is the standard pressure differential for measuring ACH in LEED for Homes.
Why not the other options?
[Reference: LEED Reference Guide for Homes Design and Construction, v4, EA Credit: Air Infiltration, p. 124., C. 75 pascals: Higher pressures are not used, as 50 pascals is the industry standard for consistency.Reference: LEED Reference Guide for Homes Design and Construction, v4, EA Credit: Air Infiltration, p. 124., D. 100 pascals: This is too high and not used in residential testing standards.Reference: LEED Reference Guide for Homes Design and Construction, v4, EA Credit: Air Infiltration, p. 124., TheLEED AP Homes Candidate Handbookemphasizes EA credits, including air infiltration testing, and references theLEED Reference Guide for Homes Design and Constructionas a key resource. The exam is based onLEED v4, ensuring the relevance of the 50-pascal standard., References:, LEED Reference Guide for Homes Design and Construction, v4, USGBC, Energy and Atmosphere Credit: Air Infiltration, p. 124., LEED v4.1 Residential BD+C, USGBC LEED Credit Library, accessed via LEED Online (https://www.usgbc.org/credits)., LEED AP Homes Candidate Handbook, GBCI, October 2024, p. 12 (references study resources and exam scope based on LEED v4)., USGBC LEED for Homes Rating System (v4), available via USGBC website (https://www.usgbc.org/resources/leed-homes-design-and-construction-v4)., LEED v4.1 for Homes, USGBC, accessed via LEED Online, confirming ACH50 testing standard., , , ]
