The DOE estimates that 20-40% of the money an average American family spends on heating and cooling their home each year is wasted through uncontrolled air leakage, insufficient insulation and failing duct work. It’s no surprise then that air sealing is almost always a top priority.
Air sealing is done with a two-component closed-cell spray foam (it is important that a closed-cell foam is used to ensure proper sealing). Gaps and cracks around attic penetrations (plumbing, electrical, chimneys, etc.) are sealed with this foam. Top plates (where the interior walls connect to the attic) and basement rim joists (where the foundation connects to the floor of the house) are also major areas of air leakage and often need to be sealed. Weather-stripping around doors and windows and sealing wall outlets are also effective in reducing air leakage.