Blower Door Testing
A blower door test uses a powerful fan mounted into the frame of an exterior door. The fan pulls air out of the house, lowering the air pressure inside. The higher outside air pressure then flows in through all unsealed cracks and openings. This test is used to determine the air infiltration rate of a building. Envelope performance is so important that newer residential energy codes require testing it for all new buildings.
A blower door consists 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.
Setup and test typically takes 2- 4 hours. Testers are certified by BPI, InterNACHI or RESNET. More information can be found here: https://energy.gov/energysaver/blower-door-tests
Thermal Camera Testing
Known as Thermography, this test measures surface temperatures by using infrared video and still cameras. These tools see light that is in the heat spectrum. Images on the video or film record the temperature variations of the building’s skin, ranging from white for warm regions to black for cooler areas. This test information helps determine where the building envelope has leaks. More information can be found here: https://energy.gov/energysaver/thermographic-inspections
Duct Diagnostic Testing
A secondary test looks at the installation of air ductwork in the building. Ducts are designed to carry cold or hot conditioned air to the spaces that need it. If the duct leaks excessively, the conditioned air does not get to the right place, creating hot or cold spaces, and can result in higher energy bills if the furnace needs to run longer to keep the space comfortable. A fan is used to change the pressure in the duct so the leak rate can be determined. The newer energy codes also require this test in newly constructed buildings. Testers are certified by BPI or RESNET.
A certified energy auditor will evaluate a house to determine how well it is constructed and what is using energy in the building. Based on this information, they may be able to rate the home’s relative performance to other similar homes. An energy audit can often be used to evaluate options that could lower the home’s energy use. Audit/raters are certified by RESNET and can provide a home HERS rating. http://www.resnet.us/energy-rating
For more information: https://energy.gov/energysaver/professional-home-energy-audits