What is a “Blower Door Test?”
A blower door is a machine used to measure the air tightness of buildings. It can also be used to measure airflow between building zones, and to locate air leakage pathways. A duct blaster, similar to a blower door, tests the air tightness of duct work.
During the audit the blower door is temporarily installed onto the frame of an exterior door—typically the main entrance. While the fan pushes air outside, the air pressure inside your home is lowered. This allows for the higher air pressure outside to flow through any cracks, gaps, and penetrations. The main benefits a blower door test will identify are:
- Reduced energy usage by resolving air leakage
- Improved home comfort by reducing drafts
- Improved indoor air quality by ensuring air supply integrity