A tip from MN Dept of Commerce: Ice Dams

A tip from MN Dept of Commerce: Ice Dams


A New Year’s resolution: Do away with ice dams

Winter in Minnesota is also the season for ice dams.If your home’s roof has developed these frozen outgrowths in past winters, then the new year may be a good time to make a resolution to take action to save yourself from costly home repairs.To help you conserve energy in your home and prevent ice dams, the Minnesota Commerce Department offers these tips.

What causes ice dams

Ice dams are not caused by roofing, ventilation or gutter problems, as often believed. The real problem is a home that is leaking warm air.Due to inadequate air sealing, heat from the home’s interior gets into the attic and melts the underside of the snow on the roof. The melted snow water flows down the roof surface until reaching a cold spot such as the eaves or soffit, where it refreezes and forms an ice dam.Over time, especially with a snow-covered roof in subfreezing temperatures, more ice can build up. Eventually, water starts seeping into the home.The result? Dislodged roof shingles, sagging gutters, water-soaked insulation, stained ceilings, peeling paint, damaged plaster and even mold or structural damage to the home.

How to prevent ice dams

Because the primary cause of ice dams is air leaking from the attic, the best way to prevent them is to seal leaks with caulking or expanding spray foam, with attic insulation installed to a minimum of R-50 as space allows.An advanced home energy assessment, or audit, is your first step to preventing ice dams and making your home more energy efficient. The assessment will use equipment such as an infrared camera to identify attic air leaks and what needs to be done to seal them.A home energy audit can be arranged through your local utility, a nonprofit energy group or an HVAC professional.Once problem areas are detected, get bids from at least two licensed contractors to have the work done.

What to do, and not do, if you have ice dams

If you need to remove an ice dam on your home, the safest and most effective action is to hire a professional ice dam removal company that uses steamers.There are also some things you should not do.

  • Do not install heating cables, which shorten the life of your roof and cost money to operate.
  • Do not remove ice with chippers, chemicals or heat, which  can damage shingles, gutters and other building components.
  • Do not add roof vents, including powered vents, which will not eliminate ice dams and often make the problem worse.

To stop ice dams, the best course of action is to attack the root cause, the attic air leaks. Sealing these leaks will help stop ice dams, prevent costly home damage and save on your energy bill.For more information on preventing ice dams, sealing air leaks and adding insulation, check out the Minnesota Commerce Department’s Home Energy Guide (pages 8-20) at mn.gov/commerce-stat/pdfs/home-energy-guide.pdf* * * * * *Minnesota Energy Tips is provided twice a month by the Minnesota Department of Commerce, Division of Energy Resources. Contact the Department’s Energy Information Center at energy.info@state.mn.us or 800-657-3710 with energy questions.