How is air leakage typically measured in a building?

Air leakage in a building is typically measured using a blower door test. This method involves installing a fan in a door frame to create a difference in pressure between the inside and outside of the building. By doing so, the blower door effectively sucks air out of the building, which causes outside air to enter through any unintentional openings or leaks in the building envelope.

The amount of air that enters through these leaks can be quantified, allowing for a comprehensive assessment of the building's airtightness. This is crucial for understanding energy efficiency, indoor air quality, and overall comfort in a structure. The results of a blower door test can also help prioritize repairs and improvements to reduce air leakage.

While thermal imaging, pressure gauges, and smoke pens can provide valuable insights into specific areas and conditions, they do not measure the overall air leakage rate as effectively as a blower door test does. Therefore, the blower door test is considered the standard method for assessing air leakage in buildings.