Sealing air ducts is a DIY project that can help you save money on energy costs. Many industry professionals consider duct putty to be the best solution for duct sealing, as it is a non-toxic, fire-resistant material that does not harden and can last up to 20 years. It can be applied with a caulking gun or spatula. Additionally, installing air barriers around the ducts and smoke ducts of the attic floor can prevent air leaks between the living room and the attic, allowing for full levels of insulation.
When looking for a company to help with your duct sealing project, make sure they specialize in energy saving projects. According to the Department of Energy Standard Work Specification (SWS) guide on sealing air in gaps and roof penetrations, sealing should be done with putty, foam, or an equivalent material. Comprehensive protection against drafts includes a continuous air barrier around the entire house, in addition to caulking and sealing all holes and cracks. Sealing the ducts can increase the durability of air conditioning systems by allowing the machine to work less to maintain the air temperature.
Joints (including joints between edge joists), attic access openings, perforations, and all other openings in the building envelope that cause air leaks should be sealed with putty, sealed with joints, waterproofed, or otherwise sealed with an air-blocking material, a suitable film, or solid material. An infrared camera can be used in conjunction with fan door tests to detect air leaks and heat loss at duct and flue openings if there is a sufficient temperature difference between the unconditioned and conditioned space in the house. The anti-aircraft barrier material surrounding the ducts may include thin sheets such as rigid insulators, drywall, OSB, or plywood. Fan door tests are carried out as part of a whole-house energy efficiency test to determine if openings in the ducts and flue ducts that lead to an unconditioned space (such as an attic) have been properly sealed. Sealing the ducts helps close any of these gaps, making it nearly impossible for air pollutants to enter.
A hermetic seal should be installed around all ducts and smoke ducts installed in ceilings, walls, and floors to prevent air conditioning from leaking into unconditioned spaces. Sealing air conditioning ducts can also help you save money by preventing air conditioners from leaking through the ducts before reaching the vents or losing or gaining heat due to lack of insulation.
