In 1998, NIST published a review of commercial and institutional building airtightness data that found significant levels of air leakage and debunked the myth of the airtight commercial building (Persily 1998). Since then, NIST has expanded and maintained a database of whole building envelope leakage measurements of U.S. commercial and institutional buildings. In addition to building leakage values collected from research publications, low-energy building programs and private pressurization testing firms, the database includes basic building characteristics such as year built, building type, floor area, number of stories, location, and wall construction type for many of the buildings. The purpose of the database is to establish default values for building simulation, to estimate the energy savings potential of airtightness requirements in standards and codes, and to identify opportunities for additional improvements in building airtightness performance. This paper presents an update of the currently available airtightness data from the NIST commercial building air leakage database. The U.S. commercial building envelope leakage database now contains data for almost 350 buildings including more than 50 constructed in the past decade. The data were analysed to determine the impact on airtightness of factors such as building type and height. Significantly, recent additions to the database include numerous buildings constructed to meet the specifications of sustainable or high performance building programs such as the U.S. Green Building Councils LEED rating system as well as buildings designed and constructed with air barriers, both of which tend to correlate with lower building envelope air leakage.
Citation: Air Infiltration and Ventilation Centre
Pub Type: Journals
Airtightness, air barrier, fan pressurization test, infiltration, sustainable buildings