The $5,000 Ice Dam Mistake

You know that massive icicle hanging over your front porch? The one that looks like a winter decoration? It’s not just “weather.” It’s a warning sign that your attic is leaking heat—and it could be costing you thousands.

That icicle is the visible tip of an Ice Dam. And right now, your instinct is probably to go outside with a broom and knock it down.

Don’t do it. Hacking at the ice often rips the gutter right off the fascia or cracks your frozen shingles, turning a maintenance issue into a $5,000 repair bill. The real fix is stopping the heat loss in your attic, not fighting the ice.

Why Is This Happening? (It’s Not Just the Snow)

Ice dams aren’t caused by cold weather; they are caused by heat leaking out of your house.

1. Warm air leaks into your attic because of gaps or thin insulation.
2. That warm air melts the snow on your roof—even when it’s -10°C outside.
3. The water runs down until it hits the eaves (the overhang). Since the eaves are cold, the water freezes instantly.
4. That ice builds up into a dam. Now, trapped water pools behind it and seeps under your shingles and into your drywall.

Put the Broom Away

When you see a 4-foot icicle, the temptation to knock it down is huge. Stop. In these temperatures, your shingles and aluminum gutters are brittle.

• The Swing: One hard hit can shatter a frozen asphalt shingle.
• The Weight: Icicles are heavy. If you knock a big one loose, the sudden weight shift can rip the spikes right out of your fascia board.
• The Result: You might get the ice down, but you’ll be buying new eavestroughs in April.

Three Ways to Fix It (From $30 to $3,000)

If you have a dam right now, here are your three options, starting with the safest quick fix.

1. The Quick Fix: Melt a Channel

Cost: ~$30. Use Calcium Chloride. This is the stuff you want. It melts ice at much lower temperatures (-31°C) than salt and is safer for your roof. Look for products like Snow Joe MELT or Alaskan Ice Melter.

Do NOT use Rock Salt. Standard salt stops working at -9°C, corrodes your aluminum gutters, and ruins shingles.

How to do it: Get an old pair of pantyhose. Fill one leg with the Calcium Chloride crystals. Lay it vertically across the ice dam so it hangs over the gutter. It will slowly melt a channel through the ice, giving the trapped water a way to drain out.

Where to buy supplies in London:

• Home Depot: Look for Snow Joe MELT or similar Calcium Chloride pellets.
• Canadian Tire: Look for Alaskan Premium Ice Melter.

2. The Band-Aid: Heat Cables

Cost: $150 – $300 (plus install). You’ve seen these zigzag cables on roofs in Lambeth. They heat up and melt a path for the water to flow. This is a management tool, not a cure. It costs electricity to run, but it’s cheaper than replacing drywall.

Products to check: Waterline RoofGuard or EasyHeat ADKS kits.

3. The Real Cure: Insulation & Ventilation

Cost: $1,500 – $3,000+. The only way to stop this permanently is to keep your roof deck cold. That means sealing up the air leaks and topping up your insulation to R-60.

The Insurance Trap: Do The Math

Before you file a claim for a water spot on your ceiling, pause.

• The Risk: A single claim can increase your premiums by 15-20% for the next 5-7 years.
• The Math: If your repair costs $1,500 and your deductible is $1,000, the insurance company pays $500. But your premium might go up by $300/year for 5 years ($1,500 total).
• The Warning: Filing multiple small claims can lead to a “non-renewal” notice. Save your insurance for the catastrophic stuff (fires, major floods), not maintenance issues.

What This Actually Costs

Thinking of Selling This Spring?

If you are seeing these icicles now, a home inspector is going to see the water stains in your attic three months from now. That turns a $500 fix into a $5,000 negotiation deduction.

Don’t wait for the buyer to find it. If you are planning to list in 2026, book a “Pre-Listing Walkthrough” with us. We will help you identify these “Red Flags” before you go to market, so you protect your equity and list with confidence.