Avoid the costly collision of hot and cold and reduce the risk that ice dams will form and create a soggy mess. When heat from the interior of a building with a sloped roof escapes into the attic space, it warms the underside of the roof. Meanwhile, the roof eave outside the heated space remains at a colder temperature.
As snow accumulates on the rooftop, it melts over the warmer portion of the attic and runs down the roof. When it encounters the cold edge of the roof it refreezes. The refrozen water along the roof edge creates an “ice damming” condition, and consequently, the melted snow running down the roof begins to back up underneath the roof covering.
This water will soak the roof sheathing and leak into the attic unless there is a barrier above the sheathing. An appropriately installed secondary moisture barrier will help prevent the water from entering your property and damaging your structure and its contents.
You can prevent ice dams by ventilating and insulating your attic. But now you need to deal with the problem that exists. Here are some steps you can take to reduce the damage from an ice dam:
• Remove ice and snow from the roof to allow proper drainage. Be careful when performing this task as you can fall, be struck by falling objects or contact electrical lines. Use a snow rake to remove the snow from the ground, if possible.
• If there is an existing ice dam, melt a channel through the ice to the roof surface to create a drain path to relieve water build up.
• An easy way to do this is to fill the leg of panty hose with calcium chloride ice melter and place that on the roof. The long tube can melt a patch through the ice to allow drainage. You can refill or replace the ice melter to keep the channels open. Make sure the channel extends to the roof edge or gutter.
• You can engage the services of your roofing contractor to remove ice build up.
• If you observe water damage, hire a restoration service to dry out the walls, ceiling and structure. Not addressing minor damage can cause rot, decay and more extensive problems.
• Contact your roofer and an insulation company to correct the ventilation and heat transfer issues in your attic. This can prevent future problems.
• When replacing a roof, add an ice and water shield membrane at the edge of the roof and extend it at least five feet up the roof to protect this area against water intrusion.
• If you have suffered damage to your property, contact your Hanover Agent or Hanover Claims at www.hanover.com or 1-800-628-0250.
Source: The Hanover Insurance Group, Loss Control Dept. View a PDF of this information, suitable for printing.