Weatherization Tips

It's easy to feel the effects of a drafty door or window, but cold air can also seep into a heated home (or out of an air-conditioned home) through several other surprising sources. And even the smallest leak can rack up a big energy bill. In fact, the Department of Energy estimates that homeowners can save up to 30 percent on their monthly energy bills just by properly weatherizing their home.

While many homeowners are aware of the benefits of weather stripping doors and windows, they may overlook other common sources of air leaks. Seal these often-undetected spaces, and homeowners could see a huge difference in energy expenditures.

Chimneys are designed to let hot air escape from the house, and they do an excellent job, even when there's no fire going. When the fireplace isn't in use, keep the flue closed to prevent air from escaping. Consumers can also purchase chimney balloons that inflate to fit beneath the flue, prevent air from escaping and deflate automatically if they come into contact with heat.

In the attic, check for gaps around the chimney. Building codes require combustible materials like insulation to be two inches from a masonry chimney, so build a metal dam around the chimney for clearance. Seal with aluminum flashing and heat-resistant caulk.

SKILL LEVEL: Pro
Chimney work is wrought with tricky codes and potential fire hazards, so weekend warriors should generally steer clear.

Dryer vents and exhaust fans can whisk conditioned air out of a home and let outside air in. In homes with a kitchen exhaust fan, add a magnetic cover to prevent air from leaking in or out while the fan isn't in use. Bathroom exhaust fans should have an internal flapper damper to prevent air from coming in or out when the fan is off. Dryer vents typically have a flapper to reduce air leaks, but if the vent becomes clogged with lint, it can prevent the flapper from working properly. Check vents periodically to make sure they're free of lint, or install a dryer vent seal.

SKILL LEVEL: Pro
There are risks in making a home too airtight. It can limit the air supply for heating appliances, and exhaust fans may pull combustion gases into the living space. A professional contractor can ensure there's adequate ventilation to prevent dangerous "backdrafting."

Check for air leaks around plumbing pipes, furnace flues and electrical junction boxes. Gaps around plumbing pipe can be filled with expanding foam or caulk, and gaps around junction boxes can be caulked. Furnace flues are slightly more challenging. Pipes need to be at least one inch from combustible materials such as insulation, so seal with heat-resistant caulk and build a metal dam around the flue to prevent insulation from touching the hot pipe. Finally, determine whether or not the attic entrance is properly sealed by turning on the attic light at night and closing the door or hatch. If you can see light, use weather stripping to prevent air from escaping through those gaps.

SKILL LEVEL: It depends
Novices can handle the weather stripping, but sealing around hot pipes should be left to professionals familiar with building codes.