Blower Door Testing

What is blower door testing?  These tests determine the air infiltration rate of a building.

Blower doors consist of a frame and flexible panel that fit in a doorway, a variable-speed fan, a pressure gauge to measure the pressure differences inside and outside the home, and an airflow manometer and hoses for measuring airflow.

There are two types of blower doors: calibrated and uncalibrated. It is important that auditors use a calibrated door. This type of blower door has several gauges that measure the amount of air pulled out of the house by the fan. Uncalibrated blower doors can only locate leaks in homes. They provide no method for determining the overall tightness of a building. The calibrated blower door’s data allow the auditor to quantify the amount of air leakage and the effectiveness of any air-sealing job.

These are some reasons for establishing the proper building tightness:

  • Reducing energy consumption due to air leakage
  • Avoiding moisture condensation problems
  • Avoiding uncomfortable drafts caused by cold air leaking in from the outdoors
  • Determining how much mechanical ventilation might be needed to provide acceptable indoor air quality.