Why is air sealing important in exterior walls?
Insulation works best when air is not moving through or around it. Exterior walls typically have penetrations for electrical wiring and outlets, as well as gaps in the top, bottom, and sides of the walls that can leak warm air into or out of your home. Besides increasing your heating and cooling costs, these air leaks can introduce water vapor into your walls, potentially resulting in condensation and damage.
Typical blown-in and batt insulation don’t stop air leakage. Air leaks need to be sealed with caulk or foam before installing insulation. But if penetrations and gaps are not accessible for air sealing, like with existing walls, installation of dense pack insulation (cellulose or fiberglass) or blown-in foam insulation will provide an adequate level of air sealing.
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What is air sealing?
Air sealing, also sometimes referred to as weatherization, is all about identifying and closing up any gaps, cracks or holes around your home where air can sneak in or out.
How much exterior wall insulation should I add?
The amount of wall insulation you need is based on the size of your walls and the type of insulation that you and your contractor decide to install. Generally, exterior walls should be insulated to at least R-13.
How is air leakage stopped?
The nature of the leak and the surface to be sealed determine what type of air sealing material to use, e.g. caulk, expanding foam, rigid foam board, weather stripping, etc.
Why is wall insulation important?
Wall insulation, like attic or floor insulation, is used to keep your indoor climate in and the outdoor climate out. If you’ve been in an old house, then you know how drafty they can feel, or even the opposite, how stale the air can feel. One of the ...
Where are the best places to air seal?
A few gaps and cracks around your home may seem insignificant, but the truth is, all those small spaces add up. All together, they are equivalent to leaving a window open all year long. Spots near windows and doors may be the easiest to spot, but ...