Code Readiness Multifamily Air-sealing Research: Data Brief on Preliminary Results from Blower Door Diagnostic Testing

There are several studies describing indoor air quality (IAQ) and tested air-leakage rates in multifamily buildings and the dwelling unit compartmentalization rates, but much of the work is in states located in colder climates and not directly transferable to California. Therefore, there is a general lack of California specific multifamily blower door testing research into actual air-leakage rates of multifamily buildings. To address this knowledge gap, the Code Readiness research team is currently recruiting multifamily buildings throughout California and conducting blower door testing to measure dwelling unit total leakage compartmentalization rates (CFM₅₀/ft²-total), leakage through the exterior surfaces only of the same dwelling units (CFM₅₀/ft²-exterior), and whole building leakage rates (ACH₅₀, CFM₅₀/ft²). This data brief presents interim findings from the first round of buildings tested. Participant recruiting is on-going and additional buildings are anticipated to be tested through 2023. The project team will prepare a report following the conclusion of these additional air-leakage tests. The report will be updated to include data from these additional buildings as well as additional analysis to investigate correlations between building characteristics and measured leakage rates.