With ten more weeks of winter still to come, we are sure to find a few snowstorms in our future. The next time it snows, do yourself a favor and take a look at your roof. Does the snow cover your roof evenly or does it melt in the center and remain visible only towards the eaves? Do you find that large icicles develop from your gutters or roof edge after a few days? These are visual signs that your home is forming ice dams.
Ice dams are formed when warm air escapes into your attic and heats/melts the snow on the roof. When the water from the snow melt reaches the eaves or gutter area, it gets colder again (no longer effected by the warmer attic temps) and freezes along the edge. Ice begins to build up along the edge, with water accumulating behind. This water can continue to build up and eventually seep through the roof, causing damage.
This video illustrates the process very well.
Ice dams can be prevented by making sure that heat from your home is not escaping into your attic. An energy audit from a local service provider can help give you information on where air leaks are coming from and recommendations on how to fix, either through improvements in attic insulation or proper ventilation. In many cases in New York State, a home energy audit can be done for free – see information here from NYSERDA.
In the meanwhile, if you have ice dams that have already formed and are causing damage, you are going to want to contact a local roofing professional who can use steam to safely clear the ice blockages from your eaves.