page_title: Blower door
section_title: How blower door tests work
hierarchical_section_title: Blower door / How blower door tests work
caption_attribution_description: English: Blower door setup in doorway with a digital pressure and flow gauge
context_page_description: A blower door is a machine used to measure the airtightness of buildings. It can also be used to measure airflow between building zones, to test ductwork airtightness and to help physically locate air leakage sites in the building envelope.
  There are three primary components to a blower door: a calibrated, variable-speed fan, capable of inducing a range of airflows sufficient to pressurize and depressurize a variety of building sizes, a pressure measurement instrument, called a manometer, to simultaneously measure the pressure differential induced across the face of the fan and across the building envelope, as a result of fan airflow, and a mounting system, used to mount the fan in a building opening, such as a door or a window.
  Air tightness testing is usually thought of in residential settings. It is becoming more common in commercial settings. The General Services Administration requires testing of new US federal government buildings.
  A variety of blower door airtightness metrics can be produced using the combination of building-to-outside pressure and fan airflow measurements. These metrics differ in their measurement methods, calculation and uses.
context_section_description: A basic blower door system includes three components: a calibrated fan, a door panel system, and a pressure measurement device (manometer).
caption: Blower door setup in doorway with a digital pressure and flow gauge
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