- 1). Create an air-tight home. Turn off the furnace on a windy day, shut the doors and windows, and turn on all fans that pull air from inside the home such as bathroom fans and stove exhaust fans.
- 2). Check common areas for leaks. Light an incense stick and pass it along sites that commonly have air leaks such as door and window frames, mail chutes, dryer vents, bricks, siding, stucco, the area surrounding vents and fans, water and furnace flues, recessed lights, all ducts, electrical outlets and switches, attic entrance, plumbing and utility access, sill plates and chimney flashing. If the smoke is pulled into the cracks, heat is leaking from your home.
- 3). Check for light leaks. In the evening, shine a flash light in all potential leak locations and have another person stand outside of the home and look for light leaks. The light shows where air is getting through.
- 4). Check the weather stripping on your doors. Shut your household doors with a piece of paper positioned at the frame. If the paper can be removed without opening the door, air and heat are leaking from your door.
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