What is a Blower Door Test?

A blower door is a home energy assessment tool to measure and find the air leakage in your home. The blower door frame attaches to an exterior door of your home, and is attached to a powerful fan. This fan pulls air from your home to slightly change the indoor air pressure, which forces outside air through unsealed areas of your home. As air quickly flows in from the outside and is pushed through your home, a home performance contractor can determine where outside air is infiltrating your home and how unconditioned air from your basement or crawl space can create drafts in your main living area.

The Greater Cincinnati Energy Alliance requires a blower door test as a part of every home energy assessment to determine where air sealing, often one of the most cost-effective home energy improvements, can be completed.