Have you noticed icicles forming along the edges of your roof? These sparkling beauties of nature can cause a major problem for your house. When snow builds up on the roof, melts, and then refreezes at the roof’s edge, you get a build up of ice called “ice damming.”
During the thaw cycle, the water from these ice dams can leak into the house and can cause various degrees of damage. It may appear as a brown stains on the ceiling, loose roof shingles, or sagging gutters. This kind of damage is visible and you can repair it when you see it.
More serious damage, however, may go unnoticed for some time. The water seeping into your house can work its way into insulation. When insulation gets wet, it compresses, resulting in lower R-values. This means you end up paying more to heat your home. Therefore, it’s important to prevent ice dams from forming.
What causes them?
Ice dams can form when as little as 1 to 2 inches of snow accumulate on the roof, especially if the snowfall is followed by several days of sub-freezing temperatures. The lower part of the roof surface is below freezing while the upper roof surface located directly above your living quarters is warmer. The escaping heat warms this section of the roof, melting the snow.
What can be done?
Here are some suggestions to prevent ice dams:
- Make sure that gutters are empty of debris so melting water flows down and away from the house
- Check your attic to see that you have adequate ventilation.
- Insulate your attic to the current standard in Northern US of R-38Use a roof rake to remove large snow accumulations
- Install roof heat tape in areas with persistent problems
Check after a heavy snow and thaw cycle to see if ice dams are forming on your roof. The sooner you find the problem, the sooner you can get it fixed.