It can be pricey to heat or cool a home. By checking the home’s energy efficiency, you might unveil some ways to trim monthly costs.

You don’t necessarily need a pro to assess your property’s energy deficiencies. With a little elbow grease, you can get a good sense of where your home is leaking hot and cool air.

Inspect exposed ducts. They may not work efficiently if they’re dirty, have small holes, or if they pass through unfinished portions of the home and aren’t insulated. Look for whether intersections of duct pipe are joined correctly. Since ducts are typically made out of thin metal that easily conducts heat, uninsulated or poorly insulated ducts in unconditioned spaces can lose 10 percent to 30 percent of the energy used to heat and cool your home.

Look for stains on insulation. These often indicate air leaks from a hole behind the insulation, such as a crack in an exterior wall.

Check insulation R-value or thickness. Where insulation is exposed (in an attic, unfinished basement, or around ducts, water heaters, and appliances), use a ruler to measure thickness, recommends the Department of Energy. Use an online insulation calculator to compare your results against those suggested for your region. Only a professional’s thermographic scan can reveal if insulation is consistent within a wall; it can settle or may not be uniformly installed.

Check your home’s exterior envelope. Hold a candle or stick of incense near windows, doors, electrical outlets, range hoods, plumbing and ceiling fixtures, attic hatches, and ceiling fans in bathrooms. When smoke blows, you’ve got a draft that may need caulking, sealant, weather stripping, or insulation.