An energy audit includes a series of tests, including the blower door pressure test (shown), that tell you the efficiency of your heating and cooling system and the overall efficiency of your home. On the basis of the test results, the auditor will recommend low-cost improvements to save energy and larger upgrades that will pay you back within five to seven years. Audits take two to three hours and cost $250 to $400, but if you set one up through your utility company, you may be eligible for a rebate.
To find out where warm air is escaping into your attic, look in your attic for insulation that has darkened (the result of filtering dirty air from the house). In cold weather, you might even see frosty areas in the insulation caused by warm, moist air condensing and freezing as it hits the cold attic air. For step-by-step information about sealing attic leaks, visit familyhandman.com and search “seal air leaks.”
According to energy experts, electrical boxes that hold switches or outlets are major sources of heat loss. Foam gaskets ($3 for a pack of 12 at home centers) won’t completely seal the boxes, but they’ll help. They’re quick to install— just take off the cover plate, stick the gasket over the box, then put the plate back on.
Sealing leaky joints in heating ducts is easy, cheap, and can reduce your energy costs by hundreds of dollars a years. Simply buy aluminum-colored silicone caulk and caulk every joint in rectangular ductwork (clean the joints first with a household spray cleaner and a rag to remove dust). Use the caulk to seal around the take-off boots to each branch run. Buy high-temperature UL181 aluminum foil tape in the duct section of a home center and use that to seal the joints of round ductwork.
Insulating your exposed hot water pipes reduces heat loss and helps deliver hotter water at a lower temperature setting. Insulate all accessible hot water pipes within 3 feet of your water heater using quality pipe insulation or a pipe sleeve. Place the pipe sleeve so the seam is face down on the pipe and use aluminum foil tape to secure the insulation to the pipe every foot or so. On gas water heaters, keep pipe insulation at least 6 inches from the flue.
Wood-burning fireplaces can warm up a room, but more often, they rob a house of heat by letting it escape up the chimney. If you have a modern fireplace with a cold air intake from outside, make sure you equip it with an airtight door. If you have an older fireplace that uses room air for combustion, equip it with a door that has operable vents. And only keep those vents open when you have a fire in the fireplace. Otherwise, heat will constantly be sucked out of the house.
Sill plates and rim joists are usually poorly insulated (if at all) and very leaky. So if you have an unfinished basement, grab some silicone or acrylic latex caulk to seal the sill plate. If you simply have fiberglass insulation stuffed against the rim joist, pull it out. Run a bead of caulk between the edge of the sill plate and the top of the foundation wall. Use expanding spray foam anywhere there are gaps larger than 1/4 in. between the sill and the foundation.
Storm windows aren’t new, but they’re definitely improved: New ones open and close and can be left on year-round. Some offer low-emissivity coatings to further cut heat loss. You can use low-e versions even if your windows already have a low-e coating. You’ll see the biggest payback when they’re used over single-pane windows. But don’t use storm windows over aluminum windows—heat buildup between the two windows can damage the aluminum, and drilling holes for installation can cause leaks.