Ice dams can cause leaks in a roof and damage to a home. This page can help you learn how to prevent ice dams by insulating and ventilating your attic.

Ice dams can cause leaks in a roof and damage to a home. This page can help you learn how to prevent ice dams by insulating and ventilating your attic.

• Heavy icicles at the edge of a roof are a sign that snow has melted and refrozen, potentially creating ice dams that can damage your home. Properly insulating and ventilating your attic can help to prevent ice dams.

• Ice dams form when snow that has accumulated on a roof melts, and the water that results from the melt runs down the roof and refreezes. This ridge (or "dam") of ice prevents further snow melt from running off. Water can back up behind the dam, and leak through the shingles into the house, causing structural damage, as well as mold and mildew problems.

Icicles are a sign of ice dams (Photo by MichigamMoves)

• The principal cause of the snow melt that creates ice dams is that heat from the house is escaping into the attic, warming the roof in spots. Properly insulating your attic can help to prevent ice dam damage to a roof. Adding insulation is a relatively simple project you can do yourself in a weekend. The Department of Energy's insulation recommendations can be found [http://www.ornl.gov/sci/roofs+walls/insulation/fig2.html on their website.

• In addition to insulating the attic, so that heat from the house cant escape and warm the roof, making sure that the attic is ventilated helps to ensure that the attic and underside of the roof are at the same temperature. After adding insulation, check to make sure that the insulation is not blocking the vents.

• Introduction
• Step 1: About Ice Dams
• Step 2: Insulate to Prevent Ice Dams
• Step 3: Ventilate to Prevent Ice Dams