Ice dams can’t always be prevented
Bad things can happen to good roofs. Even if your roofing system is top quality and properly installed, it’s possible for you to experience ice dams.
Ice dams occur when snow on the roof melts then refreezes at the edge of the roof. Leaks occur when the water backs up behind the ice and under the shingles.
Preventing ice dams
The chain reaction that leads to ice dams is most often caused by heat from the sun. The location and orientation of the house are key factors. To help prevent ice dams from forming:
Keep snow clear from the eaves so water can run off or stay below the roofline, instead of forming a dam.
Minimize the amount of heat escaping into the attic and melting the snow from below by ensuring that your attic is adequately insulated and ventilated.