If you’re a homeowner who appreciates having a roof over your head, particularly in the winter, then there’s something important you’ll want to know: how to prevent ice dams.
No, an ice dam isn’t made by ice beavers. (Sorry!) An ice dam is a unique (and highly annoying) winter phenomenon that occurs when heated air inside your home meets your roof.
“The warm air trapped beneath the surface of the room gradually conducts itself through the building material and raises the temperature of the roof’s surface,” says Scott Fischer, the owner of Ciel Power in Lyndhurst, NJ. The temperature increase melts the ice and snow on the roof, causing water to drip down toward the eaves (the part of the roof that meets or overhangs the walls).
Because your eaves aren’t heated by the indoor air, the temperature drops dramatically, refreezing the water along the edges of your roof. This happens again and again until you have a thick cord of ice around your roof. This ice dam, in turn, blocks water from running off your roof, which leads to leaks.
“As the dam expands, moisture and ice gradually find their way into the space underneath shingles,” says Fischer. “Eventually, it reaches the sheathing beneath the roof’s surface, where it melts and causes leaks into the living spaces below.”
Ice dams, in other words, can seriously wreak havoc on your home this winter. Yet there’s plenty you can do to keep them from happening.
Step 1: Get a snow rake
If you have a lot of snow on your roof, the simplest way to prevent ice dams is to get it off. Well, that’s not necessarily simple. But, to the best of your ability, pick up a snow rake, grab a ladder, and get to work. Snow rakes won’t damage your shingles, plus they come with an extra-long handle so you don’t have to climb around on your icy roof (a surefire way to end up in the hospital). So take your time and be safe.
Step 2: Prevent air leaks
Don’t let warm air reach your roof. Hunt for leaks on the underside of your roof around unsealed attic fans, ductwork, electrical conduits, and otherwise. You should also check for leaks in the floor of your attic. If you find any, grab your caulk gun and fill in those cracks. This will reduce the amount of heat making its way upstairs and out onto your roof.
Step 3: Add insulation
An attic with no insulation (or poor or insufficient insulation) is a prime breeding ground for an ice dam. So consider adding more to keep your eaves ice-free, your home toasty, and your energy bill low. As for the cost, stuffing some fiberglass insulation into a 35-by-30-foot attic will cost an average of $1,268. But not only will you save on energy bills, you’ll also recoup 116.9% of your costs if you decide to sell your home, according to Remodeling Magazine’s Cost vs. Value Report. Hey, that’s more than you paid! Not bad.
Step 4: Update your recessed lights
One surprising culprit for ice dams? Outdated recessed lights sporting incandescent bulbs. Not only do these extra-hot bulbs heat up your attic, but the ventilation system embedded in the fixture also allows even more warm air through. Replace these bulbs with modern LEDs to keep your attic nice and cool (and save on your energy bill, too).
Step 5: Increase ventilation
One way to cool down your attic is to increase the amount of air flowing from the outside through it—and that can be done by adding soffit vents (perforated screens that hang below your roof’s bottom edge) and ridge vents (small covered vents near the peak of your roof). That way, cold outside air flows through the soffits and up through the ridge vents up top. (Bonus: Better ventilation means less moisture in your attic year-round.)