How to Tell If Your Roof Ventilation Is Causing Ice Dams

Bad Attic Airflow Can Lead to Big Winter Problems

Ice dams don’t start on your roof—they start in your attic. Poor ventilation causes warm air to rise and melt snow unevenly, leading to ice buildup along your roof’s edges.

Here’s how to tell if your ventilation system is the hidden culprit behind winter roof problems.

🌬️ Signs Your Attic Isn’t Ventilating Properly

Watch for:

• Frost buildup inside the attic

• Musty smells or moisture on insulation

• Uneven snow melt on your roof (melted top, snowy edges)

• Ice dams forming near gutters or valleys

• High heating bills during cold weather

These all point to trapped warm air causing snow to melt too soon.

🔁 How Proper Ventilation Prevents Ice Dams

A balanced ventilation system pulls in cool, dry air through soffit vents and releases warm, moist air through ridge or gable vents. This helps:

• Maintain a cold roof surface

• Reduce snow melt

• Prevent condensation and attic mold

• Improve shingle longevity

🧰 What to Check

• Are your soffit vents blocked by insulation?

• Do you have a working ridge vent or gable exhaust system?

• Is your attic insulation adequate and evenly installed?

A professional inspection can confirm airflow is working as intended.

🏠 Book a Winter Ventilation Checkup

At Twin Bridge Roofing and Construction, we inspect both your roof and attic to identify ventilation issues before they cause leaks and structural damage.

📞 Call (309) 948-4126
🌐 Schedule at www.roofqc.com

Don’t just treat the ice—fix the airflow behind it.