As roofing contractors located in Colorado Springs, we often receive calls from homeowners who are experiencing leaks from ice damming. Ice damming is the buildup of ice on the eaves of roofs during winter conditions. Ice damming can cause major damage to the roofing material, as well as water damage to the interior of the home. Ice damming usually occurs on the north facing slopes of homes that sit above 7,000’ in elevation. Although a Roofer is often the first person that a homeowner calls when they experience ice damming, this problem has more to do with what is occurring under the roof than on it.
What Causes Ice Damming
Ice damming is caused by uneven roof deck temperatures, which in turn is caused by escaping heat from the living area that makes its way up into the attic. When warm air from the living area escapes into the attic, the warmer temperatures transfer to the underside of the roof deck, which will then cause the snow that is on the surface of the roof to melt. Water from the melting snow will then run down the roof slope until it reaches the area over the eaves, where it freezes again due to the cold, outside air that exists under the soffits. As this cycle repeats itself, the ice will grow thicker and higher up the roof slope. This migrating ice will then work its way under the roofing materials and can cause major damage to, both, the exterior and interior of the home.
How to Stop Ice Damming
The first step to preventing ice damming is to reduce the amount of warm air that is getting into the attic space. This is primarily done by insulating the attic floor, which will help prevent warm air in the living areas from rising into the attic and heating up the cavity beneath the roof deck. Just as important as insulating, is sealing around any penetrations in the attic floor. This would include gaps around can lights, attic access openings, and HVAC piping etc. An Insulation Company can help identify these areas and complete this task.
Once you have prevented warm air from reaching the attic space, the next step is to ensure that your attic is well ventilated. Proper attic ventilation will create a flow of cool, outside air that will stop warm air from collecting in the attic space and keep attic temperatures equal to outside temperatures. A cooler attic will stop the uneven freeze/thaw cycle from occurring and will prevent ice damming.
Electrical Heat Cable
In cases where the attic area cannot be insulated or sealed, due to lack of access, the next best option is the use of Electrical Heat Cable. Heat Cable kits are available at Big Box hardware stores and are installed directly onto the roof surface. After installing on the roof, one end of the cable is then plugged into an exterior, electrical outlet, which can be controlled by a thermostat. The use of Electrical Heat Cable is not the best method for preventing ice damming but can be used when there are no other options. Obviously, the best time to take measures to defeat ice damming is during the original construction of the home, but if this has not been done, the above steps can be taken to reduce the chances of ice damming occurring on your roof.