Blower Door Test

Definition: CHP's professional energy auditors use blower door tests to help determine a home's airtightness. A blower door is a powerful fan that mounts into the frame of an exterior door to help determine the air infiltration rate of a building. The fan pulls air out of the house, lowering the air pressure inside. The higher outside air pressure then flows in through all unsealed cracks and openings. CHP uses a calibrated blower door that has several gauges that measure the amount of air pulled out of the house by the fan. The data collected from the blower door allows the auditor to quantify the amount of air leakage and the effectiveness of any air-sealing job. The auditors use a “smoke pencil puffer stick” to help identify drafts and air leaks as the “smoke” moves with air movement.