The next time you see a home fringed with icicles, ask yourself how so much water got stuck on the roof. Icicles may seem elegant, but they may indicate a serious problem: Ice dams.
An ice dam is a thick ridge of ice formed at the edge of a roof. Ice dams prevent proper drainage, which leads to the build up of moisture and weight. If too much water and snow accumulate behind an ice dam, it can permanently damage the roof. Ice dams also affect homebuying and homeselling.
How Ice Dams Form
Ice dams form when snow on the upper portion of a roof melts, descends the roof, and refreezes before reaching the gutter. This generally happens because of temperature variation of a roof. Poor insulation, concentrated ventilation, and even simply uneven shading can cause a roof’s temperature to vary. The University of Minnesota knows a little bit more about Ice Dams then we do: Check out their comprehensive article on ice dams and see the diagram below:
How to Remove Ice Dams
We’ll get to prevention next, but if ice dams have already formed then it’s time to take action. Here are a few quick solutions:
- A Roof Rake: Use a roof rake to remove accumulated snow from the roof. This will prevent the ice dam from growing, and give it a chance to melt away.
- A sock of Ice Melter: Fill a nylon stocking with calcium chloride ice melter and lob it onto the roof perpendicular to the edge. The stocking extends the ice melter up the roof, and helps it stay in place.
- Freeze the Water:Ice dams cause leaks. So while it may seem counterintuitive, freezing the water as its melting will keep it from entering the house while a more permanent solution is devised. To do that, use a fan to blow cold air against the underside of the roof from within the attic.
There are many other resources for how to fix ice dams. Check out this video from Traveler’s Insurance to learn more: How to Remove an Ice Dam (Traveler’s Insurance)
How to Prevent Ice Dams
It may seem like ice on a roof is just part of living in cold climates. But ice dams are preventable. Here are three ways:
- Improve insulation: Improved insulation can help regulate the temperature of the roof. Insulation prevents warm air from inside the house heating portions of the roof unevenly. If the entire roof is one temperature, even if it’s below freezing, ice dams will not form.
- Install a roof vent: Like insulation, a roof vent will prevent warm indoor air from unevenly heating the roof. When warm air to escapes through a vent, its heat will not be absorbed by the roof.
- Use heated Cables: Heated cables can attached the lower edge of a roof in a zig zag pattern. When turned on, they’ll prevent ice from forming and melt any ice that does form. These are best installed by a professional.
All homeowners should pay attention to an ice dam if it forms, and have a plan for preventing them in the future. There are numerous professional companies who specialize in ice dam removal and prevention, so if you’re not up to the task don’t hesitate to ask for help. The money spent now will save much more in the future.