Something wrong with your roof this winter?

Most winter roof trouble starts inside the house. Heat leaks into the attic and warms the roof deck, snow melts on the warm part, and the water freezes again at the cold edge. That ridge of ice is an ice dam, and the water behind it can find its way under shingles and into ceilings and walls. University of Minnesota Extension traces the heat mainly to air leaking from the house into the attic.

So there are two jobs, and they often go to different businesses. The first is dealing with what is happening now: removing the ice, getting heavy snow off, stopping a leak, or covering storm damage. The second is fixing the cause: sealing the attic air leaks and adding insulation so the snow stays frozen.

For the ice that is already there, the Minnesota Department of Commerce recommends a professional removal service that uses steam once water is coming in, and warns against chipping, chemicals or open heat. Raking snow from the lower roof helps, though a rake can scuff shingles. Climbing onto a winter roof is the step that hurts people; leave it to a crew with the right gear.

For the cause, start with an energy assessment that tests the attic for leaks. Seal first, then insulate; the state recommends at least R-50 where space allows. Xcel Energy customers may qualify for rebates on the work. The state also advises against heat cables, which shorten a roof's life and add to energy costs, and against adding roof vents as a cure.

Before you hire, check the license. Minnesota requires a state license for roofing, and a roofing license does not cover gutters, soffits or fascia, which need a building contractor or remodeler license. Look a business up on the Department of Labor and Industry's license search. After a storm, remember that a contractor cannot offer to pay your deductible, and that you can cancel a roofing contract within 72 hours if your insurer denies the claim.