During the winter months, and particularly after snow storms, ice dams can start to form. An ice dam is a ridge of ice that forms at the edge of your roof and prevents melting snow from draining off. Ice dams can be dangerous to your home. They can:

  • Tear off your gutters
  • Loosen shingles on you roof
  • Cause water to back up under your shingles and drain into your home

Water that can not drain off properly works its way under your roof covering and flows into the attic. From there it can seep through insulation, ceilings, walls and other areas causing peeling paint, stained and sagging ceilings, warped floors and even mold and mildew.

Ice Dam Diagram

What Causes Ice Dams?

Ice dams form when indoor heating rises through your ceiling into the attic and warms the roof surface. Snow on the heated part of the roof melts and flows down until it meets the part of the roof that is below freezing (>32 degrees). At that point, the water freezes into an ice dam.

How to Prevent Ice Dams from Causing Damage

To prevent ice dams from endangering your home, you’ll need to keep the temperature in your roof and eaves consistent. You can do this by:

  • Adding insulation to your attic floor
  • Ventilate eaves and ridge
  • Exhaust to the outside through your roof and or walls, never through a soffit
  • Seal and insulate ducts
  • Cover your attic hatch
  • Add or repair flashing around chimneys

Completing the items listed above will help you to enjoy an ice dam-free winter while saving on energy costs. Not sure if your home has the right amount of insulation? Use a calculator or hire a licensed contractor to service your roof.