A blower door and duct test are commonly performed together to assess the energy efficiency and air tightness of a building. Here’s what each test typically involves:
Blower Door Test:
1. Blower Door: A blower door is a specialized device that consists of a powerful fan mounted on a temporary frame that fits into an exterior doorway of the building. The fan is used to create a pressure difference between the inside and outside of the building.
2. Pressure Measurements: During the test, pressure gauges are installed to measure the pressure differentials between the inside and outside of the building. These measurements help determine the air leakage rate.
3. Air Leakage Identification: To detect air leaks, a smoke pencil or a thermal imaging camera may be used. These tools help identify areas where air is infiltrating or exfiltrating the building envelope, such as gaps around windows, doors, electrical outlets, and other potential leakage points.
4. Data Collection: The blower door test provides valuable data on the air infiltration rate, which is quantified as air changes per hour (ACH). It helps assess the overall air tightness of the building envelope and provides a baseline for energy efficiency improvements.
Duct Leakage Test:
1. Duct Testing Equipment: Duct leakage testing involves the use of specialized equipment, such as a duct blaster or a similar apparatus. This equipment is used to pressurize or depressurize the ductwork system.
2. Seal-off: The registers and grilles in the building are sealed off to prevent air from escaping through them during the test.
3. Pressure Measurements: Pressure gauges are installed to measure the pressure differentials within the duct system. By pressurizing or depressurizing the ducts, the test determines the amount of air leakage occurring through the ductwork.
4. Data Collection: The duct leakage test provides information on the overall leakage of the duct system, typically expressed as a percentage of the total airflow capacity of the system. It helps identify areas where the ductwork may require sealing or repair to prevent energy loss and improve system efficiency.
By conducting both the blower door test and the duct leakage test, professionals can evaluate the overall energy efficiency of a building, identify air leakage points, and recommend improvements to enhance comfort and reduce energy consumption.