Punxsutawney Phil may have a predicted an early spring, but you can’t always rely on a groundhog for accurate weather forecasts. In the event we still have a few more weeks of winter, it’s a good idea to be aware of ice dams and how to prevent them.
An Ice Dam is a hump of ice that forms at the edge of a roof under certain wintertime conditions and can damage both your roof and the inside of your home. It will put gutters and downspouts at risk too.
Ice dams (and icicles) form when the snow melts, runs down your roof and refreezes near the edge. This only occurs when part of your roof warms to above 32 degrees F, warm enough to melt the snow, while the roof edge remains below freezing. This scenario is often the result of a warm attic. In most homes, heat escapes through ceilings into the attic and warms the wood and shingles directly above it. Although the outdoor temperature is below freezing, the snow melts over the warmed section of roof. When the meltwater runs down the roof, it hits the cold edge not warmed by the attic. There it freezes, creating a rim of ice. This rim of ice can grow, trap more water behind it, the water is forced under the roof shingles where it can linger and eventually cause leaks.
To help prevent ice dams from forming:
- Increase insulation on attic floors and all ceilings (12” to 14” is recommended)
- Seal up any causes allowing heat to escape into the attic from the home’s heated space
- Ensure the attic is properly ventilated with roof and soffit vents, this allows the warmer air to be replaced by colder air in the attic space and helps prevent ice dams
- Periodically inspect the roof drainage system to ensure there are no drainage issues with gutters and downspouts.
After a snow:
- Keep snow accumulations on the roof to a minimum to help prevent ice dam formation
- Use a snow roof rake to remove accumulated snow from areas of the roof that can be reached
- Consult a professional roofing contractor to have snow removed from steep roofs