In the average home, more than half of the conditioned air inside leaks out every hour, and an equal amount of unconditioned outdoor air gets drawn in to replace it. Finding and sealing air leaks in the envelope is vital to control that air exchange to improve your home's overall energy efficiency and boost your comfort.Identifying Where Leaks Occur
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Air leakage usually occurs through gaps and cracks in the envelope that added together can have the same effect as leaving a window wide open year round. To find leaks, hold up a smoke pencil or burning stick of incense and watch the smoke column. If the smoke wavers in any of these areas, you've located a leak that needs sealing:
Window and door frames.
Crown moldings and baseboards.
Electrical outlet plates and light switches.
Appliance ventilation and exhaust fans.
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