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NIST Air Leakage Calculation Tools for Commercial Buildings



Lisa C. Ng, Shrestha Som, William S. Dols, Steven J. Emmerich


The Department of Energy (DOE) estimates that air leakage (or “infiltration”) through building envelopes accounted for 6 % of the total energy consumed by commercial buildings in 2010 (DOE 2014). Air barrier requirements are now included in ASHRAE Standards 90.1 and 189.1. Given the significant energy impacts of unintended infiltration on building energy use, the National Institute of Standards and Technology (NIST) has been developing tools to better account for infiltration in building energy models. This paper briefly describes the tools, their applications, and limitations. All of the NIST-developed tools described herein are publicly available


Ng, L. , Som, S. , Dols, W. and Emmerich, S. (2019), NIST Air Leakage Calculation Tools for Commercial Buildings, Other, National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed May 28, 2024)


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Created December 9, 2019, Updated December 31, 2019