Ice Dam

Definition: A build-up of ice along the eaves of a roof that prevents melting snow from draining off. Ice dams can cause water to back up under shingles, leading to leaks, water damage, and potential roof structure compromise.

Risks and Damage:

• Roof Damage: The constant freezing and thawing cycle associated with these frozen ridges can cause shingles to lift and deteriorate, leading to potential leaks and roof damage.
• Water Infiltration: Water backed up behind an ice dam can find its way into the attic, walls, and ceilings, causing stains, mold growth, and structural damage to the building.
• Gutter Damage: The added weight of the frozen ridge can strain the eavestroughs (gutters), causing them to pull away from the roofline or even collapse.

Prevention of ice dams:

• Proper Insulation: Ensuring the attic is well-insulated can help maintain a consistent roof temperature, preventing the formation of these dams. Insulation reduces heat loss from the living spaces below, keeping the roof cooler and less likely to melt snow unevenly.
• Ventilation: Adequate attic ventilation helps regulate temperature, allowing cold air to circulate and preventing heat buildup that can lead to ice dams. Ridge vents, soffit vents, and other ventilation systems can improve airflow and reduce the risk of frozen ridge formation.
• Ice and Water Shield: Installing an ice and water shield under the shingles at the roof’s edge provides an extra layer of protection against water infiltration. This membrane is designed to prevent leaks in areas prone to frozen ridge formation.
• Heat Cables (ice melter): In some cases, heat cables can be installed along the roof’s edge and in gutters to prevent ice from forming. These cables help melt snow and ice, allowing water to drain properly before it can create a dam.

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