Simple leaks can sap home energy efficiency by 5% to 30% a year, according to the U.S. Department of Energy. That means it pays to seal up gaps with caulking and weatherstripping.
Take a close look at places where two different building materials meet, such as corners, around chimneys, where pipes or wires exit and along the foundation. Use the incense test: carefully (avoiding drapes and other flammables) move a lit stick along walls; where the smoke wavers, you have air sneaking in. And heating or cooling sneaking out.
In another method, have someone on the outside blow a hair dryer around each window while you hold a lighted candle inside. If the candle flickers or goes out, you need to caulk or weather strip around the frame.
Low-income households can qualify for an average of $6,500 worth of weatherization improvements to their homes through government programs administered by each state. Find out about your state's program by contacting local energy agencies.
> Related: Complete Home Energy Makeover
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