To achieve Passivhaus certification, the homes have to achieve a minimum air tightness level of 0.60 ACH 50, which is five times “tighter” than the 3.0 ACH 50 required of new Maryland code-built houses.
In these images, Robert Champ of Edge Energy operates a blower door, which pressurizes and depressurizes the house to test air-tightness and spot leaks. The initial blower door test, conducted after the modules were installed on site, was 0.36 ACH 50. This initial blower door test provides a crucial window to spot any glaring air leaks before they are covered in other building materials and become more difficult to access. The homes’ final blower door test, completed after construction was wrapped up, was 0.35 – below the Passivhaus requirement of 0.6.