Ice dams are caused from melting snow and ice on your roof. The snow melts, and once the melt refreezes in your gutters and downspouts, the ice dam starts to form. Although we can’t always prevent the occurrence of an ice dam, we can slow the process. Let’s first discuss the causes before we get into ways to help prevent water from entering your home.
Snow acts as an insulator on your roof, and this will allow your roof to heat up and speed the process of melting snow. Daytime sun will also warm the roof. If the water can’t escape the roof it will puddle behind the ice, and eventually find its way into your home or building; though many homes have an ice and water shield under the shingles to help prevent water intrusion. As water freezes overnight, the ice dam moves up your roofline. Eventually, the ice will move beyond the ice and water shield which then leads to interior water damage. Typically, an ice and water shield will be installed 3-feet up your roof past the exterior wall.
Why do some homes have iced-up gutters and others do not? Simply put, the homes that aren’t iced-up with icicles hanging from their gutters are typically better insulated and have better ventilation. You may notice newer homes are ice free, though older homes may need more insulation as it can settle and lose its thermal resistance. The resulting heat loss from the home into the attic can also speed up the melting of snow. Improper ventilation may trap the heat inside the attic space as well.
What can you do to limit my risk of ice damming? The most effective long-term solution is to eliminate heat sources in the attic by properly insulating and venting the attic. The underside of the roof should be near outside temperature. Heat sources in your attic can consist of: heating ducts, canned lights, and bathroom fans that vent into the attic space.
Some have asked if installing heat coils is a good idea to melt the ice. If you spend your time and money on insulating and venting you shouldn’t need heat coils. Heat coils are more of a band-aid fix rather than a permanent solution. Plus, consider the cost of energy to run the heating coils; electric costs can get very high.
If you are questioning the effectiveness of anything mentioned above, don’t hesitate to contact us. More than likely, if you are suffering water damage from ice damming, one or more situations are occurring.