What is an ice dam?
An ice dam is the water that freezes at the bottom edges (eaves) of your roof. They build up when your home doesn’t have enough insulation, or it was installed improperly. They’re a sign that you’re wasting energy during the Winter – and spending big bucks to do it. Left alone, ice dams can damage your roof and gutters, and leak water into your home!
Why do I have ice dams?
If you have ice dams at the bottom edges of your roof, it’s because you’re having insulation issues. Heat rising from your home that manages to get through your insulation melts the snow on your roof, which travels down as water to the colder parts of your roof then re-freezes.
Do you tend to have very large icicles coming down from your roof overhangs and gutters? This is often a sign that you also have ice dam issues.
Here’s do ice dams form?
- You heat your home during the winter.
- Because you don’t have enough insulation, or the insulation is insufficient, the heat is able to rise up into your attic.
- This rising heat warms your roof, melting the snow on top.
- This melted snow drains down to your overhangs, which are still colder since no heat rises up from below them.
- The melted snow freezes up again at the bottom edges of your roof, building up as more and more melted snow drains down from your roof.
- This ice at the bottom edges of your roof is called an ice dam.
How do ice dams damage my home?
When water freezes into ice, it expands. As the water draining down to the bottom of your roof freezes and expands, it can often expand in such a way that it gets underneath your shingles. This can damage your shingles, and leave weak spots which leak water into your home not just during the winter but year-round.
Ice dams can also damage your gutters. The water can freeze between your house and your gutters, pushing them away from your home. The weight of the ice can weigh down your gutters, causing damage and also misalignment. If your gutters become misaligned – or tilted in the wrong direction – they won’t divert water to your downspouts. Instead they’ll simply overflow at the opposite end or at a corner, draining water where they aren’t supposed to, and only inches away from the base of your house. This often leaves wet spots on walkways which can re-freeze during the winter, causing serious slip-and-fall hazards.
How do I prevent ice dams?
To prevent ice dams, you need to ensure your attic is properly insulated. You’ll have to minimize heat leaks, and ensure you actually have enough insulation in general to prevent heat from rising through. If the heat doesn’t rise through your attic insulation, it won’t heat your roof, and the snow on top will melt much more evenly. This will also save you a bundle on your heating bill, since less heat will escape your home into your attic.