❄️ Ice Dam - The Mysterious Winter Leak… But Dry All Year Round?

Roofing Gurus Explains Why Winter-Only Leaks Aren’t Actually Roofing Problems

If your home stays perfectly dry through spring rains, summer storms, and fall downpours, then logically your roof is doing its job. So why does a “leak” suddenly show up in January, after snow, and then disappear once temperatures warm up?

It’s because winter leaks often aren’t roofing leaks at all — they’re caused by ice damming, a strictly winter phenomenon linked to insulation and attic heat loss.

Icicles hanging from the roof edge indicate ice dam formation due to poor insulation and inadequate attic ventilation.

❄️ What Is Ice Damming?

Ice damming occurs when heat from inside your home escapes into the attic, warming the upper portion of the roof. This melts the snow sitting on top.

When the melted water runs down toward the colder roof edges (the eaves), it refreezes, forming a ridge of ice. That ridge is called an ice dam.

Over time, this ice barrier prevents melted snow from draining off the roof. The trapped water backs up, working its way under shingles, soaking into the roof deck, and eventually finding its way inside the home.

To the homeowner, it looks like a normal roof leak — but the roofing system itself isn’t the issue.

Illustration showing the formation of ice dams: Snow on the roof melts due to insufficient insulation, causing water to refreeze at the edge, creating ice dams that trap more water, leading to leaks and potential damage to drywall and plaster.

🧠 Why Ice Dams Only Happen in Winter

Ice dams require a unique combination of:

• Snow is sitting on the roof

• Warm attic air melts that snow

• Freezing temperatures at the eaves

• Refreezing water that builds into an ice ridge

This process cannot happen in warm weather or during rainstorms.If your roof doesn’t leak during:

• Heavy spring rainfall

• Intense thunderstorms

• Autumn downpours

…then your shingles, flashing, and underlayment are performing properly.

A true roofing failure would leak year-round.

A winter-only leak almost always indicates:

• Insulation problems

• Attic heat loss

• Poor attic ventilation

—not a faulty roof.

🏠 What Ice Dams Can Do to Your Home

Even though the roof system isn’t failing, ice dams can still cause real damage:

• Water stains on ceilings or walls

• Wet or compressed insulation

• Mold and mildew growth

• Shingle deterioration

• Damaged or sagging gutters from excess weight

Addressing the root cause is key to preventing repeated winter damage.

🔧 How Roofing Gurus Prevent and Solve Ice Damming

At Roofing Gurus, we take a holistic approach, focusing on both roofing and attic performance:

1. Attic Heat-Loss Evaluation

We identify warm areas where heat is escaping and melting roof snow.

2. Improved Insulation & Air Sealing

The most effective long-term fix for preventing roof warming.

3. Balanced Attic Ventilation

Proper intake and exhaust ensure consistent roof deck temperatures.

4. Ice & Water Shield Installation

A self-sealing underlayment applied along the eaves that protects against water intrusion — even if an ice dam forms.

5. Gutter & Drainage Assessment

Clogged or frozen gutters can worsen ice buildup and water backup.

🧊 Roofing Gurus Final Word

If your roof leaks only during winter, the problem is rarely the shingles. It’s the attic environment — specifically insulation, ventilation, and heat loss creating ice dams.

The good news? With a proper evaluation and the right upgrades, winter leaks can be eliminated permanently.