Ice dam occurrence, during this past winter, set new records in both the cost of attempts to remove these frozen structures from roof surfaces, and the extent of the damage caused by water entering the structures. Insurance claims were in the millions and homeowners were faced with high deductibles. A recent article in New England Condominium entitled “Insuring Winter’s Woes” offered suggestions in dealing with ice dams. Such measures as heated cables and shoveling the snow from the roof were mentioned and are perhaps viable methods of dealing with ice dams after they have occurred, in spite of the potential danger.
What is an Ice Dam?
Ice dams occur when heat escapes from living areas into the attic space or rafter cavity in the case of cathedral ceilings, melts the snow on the roof and the snow melt runs down and refreezes at the cold edge of the roof. Water then backs up against this dam and finds its way under the shingles and into the structure.
The best solution is not allowing ice dams to form in the first place. This is accomplished by a proper roofing/ventilation system. Replacing shingles and installing ice and water barriers in various parts of the roof surface does not constitute a proper roofing job. Attic ventilation must also be addressed.
Current building practices have resulted in much tighter homes where the management of interior air is much more important than in the days of leaky windows and doors, which provided a natural, although energy-wasteful, ventilation.