Ice dams force water under shingles as melted snow refreezes at the eave. They can cause serious interior water damage if left untreated.
Ice dams force water under shingles as melted snow refreezes at the eave. They can cause serious interior water damage if left untreated.
How Ice Dams Damage Avon Roofs
- The Formation Cycle: Snow on a warm roof deck melts and flows toward the cold eave, where it refreezes. Ice blocks drainage and backs water up under shingles.
- Leak Barrier as the First Defense: GAF Weather Watch® or StormGuard® membranes prevent water from penetrating the roof deck at the eaves when ice dams form.
- Interior Damage Risks: Water behind an ice dam causes ceiling stains, damaged drywall, soaked insulation, and mold growth. Latent damage may not appear immediately.
- Ventilation Reduces the Risk: Adequate attic ventilation lowers attic temperature and reduces snowmelt. A balanced soffit and ridge system is the most reliable long-term prevention.
- Ice Dam Removal Costs: Ice dam removal can cost up to $4,000. Follow-up shingle repairs run $130–$9,000, and roof leak repair can reach $24,000 in severe cases.
How to Prevent Ice Dams on Your Avon Roof
Top Recommendation: Install a complete GAF system with Leak Barrier Protection and Cobra Attic Ventilation for comprehensive prevention.
Best for Budget: Address ventilation first — it’s the most cost-effective ice dam prevention strategy available.
Best for Existing Issues: Contact a professional immediately to prevent further water intrusion and assess roof or attic damage.
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Last Updated: June 2026
Sources:
- Ice dams form when membranes at the eaves are needed to stop water from getting under shingles and into the roof deck. GAF R-116: Ice Dams — Cause and Preventative Measures, GAF’s technical bulletin on how leak barrier membranes protect the roof deck where ice dams form. (2025)
- Adequate attic ventilation lowers attic temperature, which reduces the snowmelt that causes ice dams. GAF R-116: Ice Dams — Cause and Preventative Measures, GAF’s technical bulletin on how proper ventilation helps prevent ice dam formation. (2025)
- Removing an ice dam can run as high as $4,000. Angi Ice Dam Removal Cost, Angi’s cost guide covering professional ice dam removal pricing. (2025)
- Shingle repairs following an ice dam can range from $130 to $9,000. Angi Ice Dam Removal Cost, Angi’s cost guide covering follow-up shingle repair pricing after ice dam damage. (2025)
- In severe cases, repairing a roof leak can cost up to $24,000. Angi Ice Dam Removal Cost, Angi’s cost guide covering roof leak repair costs associated with ice dam damage. (2025)
