Prevent Ice Dams on Your Roof this Winter
Many homeowners are completely unaware of ice dams forming on the roof during winter — at least, until they experience serious indoor water damage and property loss. Ice dams obstruct the free flow of water from melting snow. Water pooling on the roof leaks into the attic causing structural damage, saturated insulation and toxic mold growth. As it drips further down into living spaces, a damaged ceiling and ruined personal possessions may result.
It may seem counterintuitive, but the cause of ice dams on the roof is a warm attic. Heat infiltrating the attic from rooms below rises and warms the underside of the upper portion of the roof. Snowfall on that portion rapidly melts and runoff re-freezes as it reaches the more frigid lower roof, near the eaves. A barrier of ice forms, obstructing flow into gutters. Standing water on the roof accumulates, rapidly penetrating shingles and seeping into the attic.
To prevent ice dams, make sure your roof is uniformly cold in winter:
- To ensure optimal attic air flow, verify that attic vents at the roof peak and the soffits are unobstructed (soffit vents frequently become blocked by insulation).
- To inhibit heat conduction through the ceiling, check your attic insulation for proper depth. In our climate zone, you need 12 to 18 inches of standard fiberglass batts or 10 to 15 inches of cellulose loose-fill. Insulation can be upgraded by adding additional material to existing layers to achieve proper depth.
- Direct leakage of warm air from rooms below into the attic is another cause of uneven roof heating. Use caulking to seal structural cracks and gaps at the joint between walls and the ceiling, as well as around recessed ceiling light fixtures and any plumbing pipes or vents that enter the attic from living spaces. Also, weatherstrip the attic access hatch or pull-down stairs.
At Sobieski Services, Inc., our goal is to help our customers in Delaware, Pennsylvania, Maryland and New Jersey learn more about energy and home comfort issues — especially HVAC and plumbing issues — so that they can save money and live in healthier, more comfortable homes.
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