The icicles hanging from your eaves and gutters last year may be a faint memory now. But winter is coming, and along with it one of your home's worst enemies—ice dams. Ice dams are continuous chunks of ice that form along the margins of your roof. While frozen, they're no more trouble than the icicles that hang down. But during the warmer parts of a winter day, water melting off the roof pools behind the ice then seeps back up under the shingles. Sometimes water can work its way 5 or even 10 ft. back up under the shingles. Eventually it drips through the roof into the soffits, walls, and worst of all, onto your ceilings. You'll first see rust spots on drywall fasteners, then perhaps peeling paint, sagging drywall and stains around windows and doors. Now is the best time to stop ice dams, before winter comes and before they build up. Following are a few ideas to help prevent ice dams.
1. Close up attic bypasses
In the average home, about one-third of the heat loss is through the ceiling into the attic. By stopping air leakage to mitigate ice dams, you will also save energy and reduce both your heating and your air conditioning bills.
2. Measure your attic insulation level
While you're in the attic, check the depth of your attic insulation. Building codes require about 12 to 14 in. of fiberglass or cellulose. Add more if you have less than 8 in. and have had ice dam problems in the past.
3. Add roof and soffit vents
Attic ventilation draws in cold outdoor air and flushes out warmer attic air, cooling the attic and the roof in the process