blower door test | “the big red door of truth”

A blower door test is a key component of testing a PASSIVE HOUSE's airtightness. It involves fitting a powerful fan into an exterior door frame, which then depressurizes or pressurizes the building. This test helps determine the air infiltration rate of the building envelope, allowing for adjustments to achieve the required airtightness levels for PASSIVE HOUSE certification (0.6 ACH@50 and 1.0ACH@50 for EnerPHit renovations).

For certification by the International Passive House Institute (PHI), a final blower door test is required upon project completion. However, for practical reasons, it is recommended to conduct the first blower door test after installing the air barrier and doors/windows in the exterior envelope. This early test helps detect air leaks when most areas of the building are still easily accessible, facilitating timely fixes.

need a blower door test ?

Are you in the process of building a new Passive House or renovating for EnerPHit certification? We're here to support you. Whether you require a single, one-time blower door test during your Passive House project or need help identifying air leaks after completing the building envelope, we're at your service. We can also assist with the final certification test for Passive House Institute (PHI). Contact us