Make sure you verify air tightness with a blower-door test, a definitive and demonstrative test that has become a very important part of every energy-efficient and green building program verification procedure.

I want to stress that builders need to be more proactive with this test—a simple pass/fail declaration by your energy rater overlooks opportunities presented by the test results. Challenge your site supervisors, insulators, framers, and other trades to review air tightness statistics for different models or different crews with the goal of continual improvement. Tight, tighter, tightest is a cost-effective goal. That is, air tightness is always good and can be done for very little incremental cost through simple training. For example, I recently gave a demonstration of a blower-door test to 60 tradespeople at a high-volume builder, followed by a pre-drywall site walk to review air-sealing responsibilities. This educational session resulted in average air leakage levels to be cut in half on the houses they built in the next month without any increase in cost.

In a future article we will review the interpretation of air-tightness results; take the first step this spring by commiting to air-tightness testing in all your homes and look for consistency. Aim for continual improvement in results.