You probably already know to check your attic for leaks and add insulation to keep hot air from escaping your home. But did you know that you can lose almost as much energy through the basement? Cellars and underground spaces often get overlooked in the quest for energy efficiency, but by adding insulation and sealing leaks in your basement, you can stop up to 30 percent of the heating and cooling loss from your home.
Defeat the Chimney Effect
Hot air rises and usually escapes through the roof, but cold air can enter your house through the basement, and the two forces complement each other in what the federal Department of Energy calls the “chimney effect.”
“As hot air generated by the furnace rises up through the house and into the attic through leaks, cold outside air gets drawn in through basement leaks to replace the displaced air,” the DOE website explains. “This makes a home feel drafty and contributes to higher energy bills.”
In order to find any leaks in your basement or crawl spaces, check around the floor joists and foundation walls. In addition to obvious holes, keep an eye out for insulation that's insufficient or missing altogether. To fine-tune your search, you can use a hand-held leak detector that uses a thin trail of smoke to guide you toward any spaces where air is coming in or out.
Insulate, Insulate, Insulate
Now that you know where the leaks are, it's time to seal them. For very small holes, like cracks less than ¼ inch wide, caulk is your best bet. For bigger gaps up to three inches, spray foam insulation will do the job, working its way into seams and joints before it turns solid and expands to create a tight seal. For larger areas, fiberglass insulation is a good option to fill in the space.
Don't just concentrate on the outer walls – make sure you seal holes in the basement ceiling as well, like around spaces where wires, pipes and ducts go to the rest of your home. It's a good idea to seal the rim joist cavities for good measure even if you don't see any visible cracks or damage.
Fight Waste and Save Money
About 20 to 30 percent of treated air escapes from your house by leaks, and heating and cooling is the single largest energy expense in the average home, so you can make a big difference in your bills by tracking down gaps and holes wherever they are. If you need help finding leaks or adding insulation to your basement, call up a home services professional today.