What is an Ice Dam?

Worthington home new roof

Ice dams are ridges of ice that form along the bottom edge of a roof due to unvented heat loss inside a home’s attic space. When the upper portion of a roof is warm enough to melt snow and the eaves below are cold enough to freeze the runoff, an ice dam is born. If snow continues to melt, water will then begin to pool behind the dam. Excess water running over the edge of the dam may form icicles, but more problematic is trapped water that migrates back up the roof and under the shingles, leaving the roof susceptible to leaks, rotting, mold, ruined insulation and structural problems.


The Solution to Ice Dams

The best way to permanently prevent dams from forming is to have a well-insulated attic floor combined with adequate attic ventilation that keeps the surface temperature of the roof consistent – called a “cold roof.” Homeowners should also check the attic floor for cracks, holes and gaps around ductwork through which warm air from below can enter. These should be sealed with spray foam or a similar product.

With adequate insulation levels, no air leaks and a well-vented attic, your attic will stay cold enough to prevent ice dams. As a bonus, you’ll also save on heating costs and minimize any possible condensation in your attic during the winter months. In the summer, your top floor interior spaces will be cooler and more comfortable.

For more information about preventing ice dams, or to schedule a professional inspection of your roof and attic space to determine if Dublin, Ohio, roof repair is necessary, call the Dublin, OH, roofing experts at Muth & Company at (614) 682-3060.

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