Insulation is great for retaining your home's heat during the winter, but unless your home is properly sealed it won't perform to its best. We've blogged before about outlet and switch sealers, but because it's such a simple fix, it deserves another mention.
To get the most out of batts and blown insulation, every house needs an air barrier adjacent to or contiguous with the insulation layer. Rigid foam and spray polyurethane foam can create an effective air barrier if installed correctly (taped seams in the case of rigid foam used for wall sheathing), but some insulation, such as fiberglass batts, are very permeable to air leakage. Sealing air leaks with caulk and expanding foam and weather stripping are good options, but switch and outlet gaskets are a cheap and easy way to increase the air-tightness of your home.
Available in switch plates designs (including Decora or rocker type switches) and electrical outlets, these cheap foam gaskets can do wonders to increase the air-tightness of your home. One reader also mentioned making their own from foam meat trays.
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