Mind the Gaps: Fill Open Spaces to Help Cut Winter Heating Costs

According to the U.S. Department of Energy, 50 to 70 percent of a home’s energy use is devoted to heating and cooling. As a result, anything that could potentially make a heating and cooling system more efficient could cut energy costs dramatically. Attic spaces and areas exposed to unheated or uncooled air should be well insulated, as should exterior walls and floors.

The Energy Department’s Insulation Fact Sheet is a great tool to help homeowners evaluate their insulation needs. The site also goes into detail about what kind of insulation would be best for particular types of homes, including older homes and new construction.

But one area that often isn’t addressed is the air leaks that are always present in both new and old homes. Bruce W. Harley, technical director for Conservation Services Group in Boston, a nationally known expert of home energy conservation and author of “Insulate and Weatherize” (Taunton Press, 2002), says many insulation contractors are there to roll out blankets of stuff in the obvious spots and end up ignoring the tiny openings that can still cut efficiency. “Most contractors… have never been taught about this and it just falls through the cracks, quite literally,” he says.

The result is that the amount of heated or cooled air lost to gaps in a home’s structure can equal that of several wide-open windows.

The problem is that most of these leaks are well hidden in crawl spaces, attics or where different parts of the house join together. Other potential trouble spots include popular architectural details like drop, tray and cathedral ceilings or anywhere the heights of ceilings or floors change in relation to other parts of the house.

Even with a good amount of traditional insulation, Harley says, significant heat can be lost. Leaky ductwork alone can sap between 20 and 40 percent of a home’s heated or cooled air before it ever reaches a room. Just by adding more insulation there, homeowners can realize energy savings of between 5 and 30 percent. “Its basically getting up into the attic, peeling back the insulation that’s already there,” and filling in with expanding foam, more insulation or patching holes with plywood, he says.

For a more in-depth assessment of a home’s insulation needs, Harley suggests contacting a local energy utility to provide a whole-house energy survey. Such surveys have changed significantly since they were first offered, he says. “The days of an energy audit where someone walks into your house, looks around and hands you a piece of paper and says, ‘You can do this if you want to’ are over.”

Instead, a utility might now suggest programs such as financial incentives or will sometimes kick in a portion of the costs to do work in the house. Some also offer access to financing for insulation and efficiency improvements, as well as technical help.

Private contractors are also available to perform the same service, and can be found by region using the Residential Energy Services Network, which offers a Consumer Resources page on its Web site that lists certified professionals who offer energy rating services.