Blower Doors: What Are They and How Do They Work?
A blower door is a device used in energy testing to measure a building’s airtightness. It consists of a powerful fan mounted on a temporary frame that fits into a doorway or an exterior opening. During a blower door test, the fan creates a pressure difference between the inside and outside of the building. This pressure difference allows air leakage points to become apparent and measurable. The test helps identify areas of air infiltration or exfiltration, which can affect energy efficiency and indoor comfort.
The blower door test involves setting up the device, measuring the baseline pressure, and then either depressurizing or pressurizing the building using the fan. While the fan is running, the airflow rate is measured using instruments like a manometer or pressure gauge. This airflow measurement quantifies the amount of air leakage in the building. Smoke pencils or thermal imaging cameras can be used to locate specific air leakage points.
The blower door test can be conducted in both depressurization and pressurization modes, allowing for a comprehensive assessment of air leakage locations. Once the test is complete, the data is analyzed to determine the building’s airtightness and identify areas that need improvement. The results can be used to guide air sealing measures and improve energy efficiency.
Blower door tests are crucial in identifying air leakage points, reducing energy loss, improving indoor air quality, and enhancing the overall performance and comfort of a building.