06/12/2026
A satisfying post-project test-out. 👏
After completing this addition, we ran a blower door test to measure the home’s airtightness, and despite adding square footage, the home actually tested tighter than before. A roughly 425 reduction in CFM (absolute air leakage) and down to 9 ACH50 from 13 ACH50 (relative to building size at time of test).