Ice Dams: Causes and Prevention

Ice dams are ice deposits that form at the roof edge, which can cause damage to the roof and gutters. It can also pose risk of injury if it forms icicles. In this blog, roofing contractor Colorado Roof Toppers shares an in-depth look at ice dams, its causes, and how to deal with them.

How Ice Dams Form

Ice dams form when the roof temperature is raised to above freezing, which melts the snow on it. The resulting water then flows down and refreezes as it reaches the roof edge. As this cycle repeats, an ice dam is formed. Over time, this could spread into the gutters, and even form icicles. While not as common, heat from the sun or sudden drafts of hot air may melt the snow from above.

Causes of Ice Dams

Heat from the indoor living areas tends to rise and collect in the attic. A properly-built sloped roofing system would vent heated air through the ridges. Roof insulation would prevent residual heat from penetrating the roof deck. If the attic has insulated floors, it should keep attic heat levels to a minimum. 

Insufficient attic ventilation and insulation are, therefore, the main causes of ice dams. Instead of being vented out, heat gets trapped in the attic, which would then heat the roof deck. Since decking material and outer roofing material like asphalt shingles do not have insulative properties, it would only be a matter of time before the roof temperature rises from the trapped heat.

How to Prevent Ice Dams

You need to make sure that your attic is properly ventilated and insulated. Poorly-designed roofs would either lack ridge vents, or have ones that are too narrow. Soffit vents need to be properly sized to ensure consistent airflow. Fortunately, ventilation issues can be corrected after the roof is installed. If ridge ventilation isn't enough, your roofing contractor may recommend exhaust fans to bolster the ridge vents.

If ice dams are a recent problem, moisture may have infiltrated your attic and caused damage to the insulation layer. Most types of insulating material form clumps when in contact with water, so you may need to look into having potential roofing leaks addressed, in addition to having an insulation professional address insulation deficiencies. Also, accessories such as heated gutter covers can be useful for clearing ice dams, but this can't be installed if ice dams have already formed.

Colorado Roof Toppers is your leading provider of residential roof replacement services. Give us a call at (303) 622-0305 or fill out our contact form. We serve customers in Fort Collins, CO, and nearby areas.

by Denise Bart January 03, 2020
Gutters    Roofing