An invaluable tool for achieving high performance houses-both new and retrofit-is performance testing. Several sets of tests were run during the construction and then after the completion of the house, including overall air leakage (aka blower door), duct system leakage (Duct Blaster®), and thermal/infrared camera scans (with and without the use of a blower door to induce air leakage).

Blower door tests run near the end of the construction turned out to be quite informative on details that were missed, despite having excellent quality tradespeople. This test can be done by depressurizing the house with the fan and walking around the house, feeling for air leakage. For instance, the basement bulkhead door was disastrously leaky, despite the presence of some ineffective weather stripping.

In addition, the drainage mat under the finish slab was turned up at the base of the masonry chimney; the testing showed that soil gasses could be pulled from the space between the two slabs to the interior, so it was capped off with concrete and fire-rated caulk. After addressing these worst leakage points, the house met the original airtightness target.