How to Prevent Ice Dams

It's going to snow tomorrow. Lots of snow is going to pile up on roofs all over New Hampshire, and

at the bottoms of a lot of those roofs, ice dams are going to form. And every single one of those ice dams could have been prevented. Here's how:

The cause of ice dams is heat from indoors leaking out and causing some of the snow that's on the roof to melt. This melted snow runs down the roof until it hits the eaves (the overhang, where suddenly there's no heat escaping and everything's cold again) and quickly refreezes. The process continues until there's so much ice built up on top of the eaves that it keeps snow from sliding off. And that's not the worst part. As the ice dam grows, it can creep under shingles. Then when it eventually melts, it can leak into your house, causing water damage.

The best way to prevent ice dams in the long run? Make sure your roof is properly ventilated and your attic is properly insulated.

The best thing to do now to prevent ice dams in tomorrow's storm? If your roof is prone to getting ice dams, rake the eaves off periodically to prevent buildup. If buildup occurs, fill a nylon stocking with magnesium chloride ice melt. (Make sure it's magnesium chloride so you don't damage your roofing materials.) Toss the stocking onto the edge of your roof where the ice is forming and let it melt it off.

Tomorrow's expected to be windy, though, so with any luck, your roof will stay clear.