Air sealing is the systematic finding and sealing of air leakage points in a home or building. Electricians, HVAC contractors, and plumbers will drill and saw their way through floors, walls and ceilings, creating channels for the wires, heating ducts, water lines, and waste pipes that need to be run throughout the house. While these penetrations in the building envelope do not compromise the building’s strength, they result in air leakage that can make the building inefficient and uncomfortable.
Before sealing air leaks, they must first be located with a blower door and air duct test. Air sealing should always be performed before insulation is installed. Locating air leaks requires special equipment and training, with the objective of creating an airtight building envelope. This one-time process effectively seals for the lifetime of the building and is one of the most cost-effective means to ensuring a home is energy efficient.
Air sealing is one of the most inexpensive strategies you can employ to help you save money on your utilities and feel more comfortable as soon as it is completed. In most cases, the money spent will easily be recouped within the first year. This is one reason why it is #1 on DOE’s priority list for weatherizing homes. Your energy savings will vary based on how much air leakage you have. In some cases, with a well built home you may not realize hardly any savings, while some have saved over 20% on their bills. Not only does air-sealing one’s house help lower your utilities and make one more comfortable, it can help improve the air quality inside the home, help prevent moisture problems and prolong your HVAC system.