Ice dams on your house? You're not alone

Here’s the recipe for an ice dam:

Start with a poorly insulated attic.

Cover the roof with heavy blanket of snow.

Leave the snow in place. Wait.

This winter’s early, heavy snow was the perfect ingredient for ice dams on Northland roofs. Snow-removal companies, people who sell roof rakes and insurance companies are noticing.

“I haven’t seen these kinds of primary ice dams and secondary ice dams for 10 years,” said Ron Burcar of Burcar’s 3rd Generation Ice and Snow Removal, whose family has been in the business since 1954.

Dave Sundstrom of Sundstrom Construction, who started his business in 1978, has noticed the same thing. “I’m getting a lot of people calling … an excessive amount of people calling this year, compared to other years,” Sundstrom said. “The problem started earlier this year than it normally does.”

An ice dam forms when snow melts on a roof and freezes again as it reaches colder territory on the edges of the roof. As snow continues to melt, the water backs up behind the ice dam and looks for places to go. You can see the ice on your roof, usually accompanied by icicles.

“What happens is (the water) starts going around any kind of a gable or it goes around dormers, and that’s where it starts leaking,” Burcar said.

Steve Gohde, a hydrologist for the National Weather Service in Duluth, put it this way: “Water runs downhill. Sometimes it runs under your shingles.”

The secondary ice dams, which form halfway up the roof and can continue to the peak, “is where people can really get into trouble,” Burcar said.

The trouble manifested itself on Dec. 30 and 31 when 1.8 inches of rain fell in Duluth. “We did four houses when it rained,” Burcar said. “Everybody was leaking.”

Steve Witmer, media relations manager for Madison-based American Family Insurance, said his company has received 665 claims for ice dam damages in recent weeks, just in Minnesota.

If you have snow on your roof but not ice, it still can be a problem. Jeff Larson of Minnesota Energy Resources, a natural gas utility, said if your furnace or dryer vent through pipes in the roof, it’s important to make sure the pipes don’t get plugged by snow. Plugged vents would allow carbon monoxide to form in your house.

Air-exchange vents also should be kept free of snow, Larson said. Cold air comes in through vents in the soffits, is warmed in the attic and comes out the air-exchange vents. If the warm air is trapped in the attic, the temperature imbalance that’s created between the attic and the roof can create an ice dam.

The time to combat ice dams is in the summer, said Patrick Huelman, University of Minnesota Extension specialist for building and energy systems. “Find out where the leaks are and where the insulation is needed in the summer.”

But Huelman acknowledged that people have been taken by surprise this winter. “It’s hit a new batch of houses this year from what I’m hearing and from what I’ve been seeing,” he said.

What do you do now that it’s winter?

There’s the DYI option. Local hardware stores say they’re experiencing a run on roof rakes, which are used to pull snow off the roof from the ground. Yvonne Pilcher, a cashier at Denny’s Ace Hardware on Calvary Road, said prices range from $45 for a metal version to as much as $130 for the “Avalanche” models made in Buffalo, Minn.

Also popular, Pilcher said, is Roof Melt, a bucket of 60 tablets that can be tossed on a roof to promote melting of snow and ice. One bucket costs $20, she said.

The professionals say they can do a more thorough job. And if you use a ladder, your trip up the roof might end up in an emergency room.

Gohde said a member of his family fell off a ladder during the holiday season and was seriously injured. Burcar said he finished a snow-removal job for someone who broke seven ribs after falling off an icy roof. His crew uses harness rope grabs tied off to the roof, he said. “Our policy is if it doesn’t feel safe, it isn’t safe.”

But don’t hire just anybody, Sundstrom said. A licensed contractor is properly insured, understands roofs and knows what to look for, he said. “A handyman gets up there and he doesn’t know where to look for the vents. He damages some things and he won’t be around next summer. We will be.”

The price varies with the size of the house. A three-bedroom rambler will cost about $200, Sundstrom said.

Tags: blueprint, budgeteer, home