Air sealing is one of the most important measures for increasing the comfort, health, and efficiency of homes. It prevents air from exchanging between the attic, crawlspace, and living space while also preventing insects and rodents from entering the home. It helps to maintain the temperature of the house and may increase indoor air quality. Air exchange management is the foundation of a whole house energy upgrade.
Proper air sealing should include attic hatches, can lights, fans, and all electrical or plumbing penetrations. It should occur in attics, crawlspaces, and basements. It can be achieved in walls by dense-packing with blown insulation. Air sealing will always also consider ventilation and combustion safety.