How Ice Dams Form
Ice dams are caused by accumulated snow and uneven roof temperatures. During winter, when the upper area of a roof is warmer than the lower edge, nearest the eave or overhang, snow begins to melt and run down the roof slope. Once it reaches the colder roof edge, it refreezes, creating a block of ice called an ice dam. An ice dam prevents snowmelt from draining, causing water to pool on the roof which can eventually back-up under you shingles or cause damage to your roofing system and home's interior.
How Ice Dams Affect a Roof
Once an ice dam has formed, it can cause significant damage to your home if not removed. As water pools at the lower edge of the roof, it can begin to back up under the shingles. Once water is under the shingles, it can soak into the sheathing and roof deck.
If an ice dam breaks free and falls off the roof, it can damage both the gutter system and the shingles at the edge of the roof as well as any items, landscaping, or people around the area under it. Even if it doesn't come loose, the weight of an ice dam can cause gutters and downspouts to bend or warp.
Preventing Ice Dams
Ice dams can be prevented with winter maintenance, snow removal, proper attic ventilation and insulation.
Before winter weather arrives, have your roof properly inspected by a professional roofing contractor*. They can tell you what maintenance needs to be completed and inspect your attic for proper installation and ventilation. They can also provide specific recommendations to help you prevent ice dam damage to your home.
The answer to "can ice dams cause roof damage" is a resounding yes. Left untreated, ice dams can cause significant damage to your roof, shingles, and attic spaces. It's important to take steps to prevent ice dams from forming as well as remove snow from the edges of your roof. A professional contractor can help you determine what steps you need to take to prevent ice dams and the damage they can cause.
