This seems to be the winter of ice dams.  I personally know several people currently dealing with this issue at their homes.  The folks at Clean Energy Resource Teams have tips that can help everyone.

First, it's important to know the primary cause of ice dams.  It is not caused by faulty roofing, ventilation or gutter problems.  The main culprit 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 forms a frozen dam.

Over time, more ice builds up and then water starts seeping into the roof.

Therefore, the first step in prevention is to seal any leaks with caulking or expanding spray foam, with attic insulation installed to a minimum of R-50 as space allows.  You can call your utility company to schedule an energy audit.  They will use an infrared camera to find attic air leaks and have personalized recommendations on how to seal them.  Rebates are often available.

As the snow flies during the winter, you should also do your best to remove snow off your roof with a snow rake.

If you already have an ice dam problem, it is highly recommended that you not try to tackle it yourself.  It's best to hire a professional service who will use steam and not further damage your roof.

Three things you should never do to tackle ice dams:

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