Leakage Reduction for Large Building Air Sealing and HVAC System Pressure Effects

Building air leakage tests were conducted on six commercial and institutional buildings before and after air sealing work. Results indicate that it is possible to reduce the leakage of already tight buildings. However, the sealing potential is better for leakier buildings, unless investigators can identify concentrated leaks that are inexpensive to seal.

For many of the buildings, ignoring the effect of HVAC operation on building pressure would produce overestimates of air infiltration loads and high predictions of energy savings due to envelope air sealing. However, in some instances HVAC depressurization caused increased infiltration that would result in underestimates of infiltration and air sealing savings.

Presented at the 2013 National Institute of Building Sciences TightVent Workshop on Building and Ductwork Airtightness.