If you’ve looked up at your roof lately and seen a thick ridge of ice hugging your gutters, you aren’t just looking at a “winter wonderland” scene. You’re looking at an ice dam.
While they might look like harmless oversized icicles, ice dams are one of the leading causes of hidden home damage during the cold months.
How do they form?
It’s a bit of a “perfect storm” of physics:
- Heat Leaks: Heat escapes from your living space into the attic, warming the roof deck.
- The Melt: The snow on the upper part of your roof melts and flows downward.
- The Freeze: When that water reaches the cold eaves (the part of the roof that overhangs the house and stays freezing), it turns back into ice.
- The Dam: This ice builds up, creating a wall that prevents future meltwater from draining. That trapped water then backs up under your shingles and leaks into your walls and ceilings.
Help! I Have an Ice Dam. Now What?
If you’ve spotted a wall of ice or—worse—water dripping from a window frame, don’t panic. Here is your step-by-step action plan:
- Assess the Danger First: Never climb a ladder onto a snowy or icy roof. It is incredibly dangerous and the leading cause of winter home injuries.
- The “Sock” Trick: Fill a nylon stocking with calcium chloride ice melt (not rock salt, which ruins shingles) and lay it vertically across the dam. It will melt a channel through the ice, allowing the trapped water to drain safely.
- Use a Roof Rake: If you can safely reach from the ground, use a long-handled roof rake to remove the fresh snow from the first 3-4 feet of your roof. No snow = no more fuel for the dam.
- Check the Attic: Go inside and look for damp insulation or water stains. If you find a leak, use a fan to blow cold air directly at the underside of the roof deck where the water is coming in. This can help freeze the water and stop the flow temporarily.
- Call the Pros: If the dam is massive, hire a professional.
Take some time to walk around your home, seasonal home, cabin, cottage and business to see if you have any ice dams.