Hopefully, you remembered to clean all the leaves from your gutters during autumn. With the arrival of winter, you’ve got another problem to watch your roof for, ice dams are thick ridges of solid ice that build up on your roof’s eaves. It’s important to know how to identify ice dams and to know how to prevent and remove them as they are very destructive. Ice dams can rip off gutters, loosen shingles, and prompt water to back up and begin to leak into your house. This in turn produces peeling paint, stained and sagging ceilings, and warped floors as well as soaking your attic’s insulation, thus lowering its R-value and encouraging mold and mildew growth. While doing home inspections in Columbus Ohio and Central Ohio we often come across situations that are conducive to ice dams on roofs. Understanding how they develop is important.
Usually, ice dams are caused by a combination of subpar attic/roof ventilation and a warm attic. They commonly start or worsen after a heavy snow, because of how insulative snow is. Dams are easily aggravated by a clogged gutter system. Good thing you remembered to clean those gutters, right? The dam forms when snow melts on an upper, warm section of the roof. The water runs down the roof onto the cold eaves, where it then freezes into ice. The ice gathers as more snow melts, and can back up under the shingles where it melts again, this time soaking the roof sheathing and leaking into the attic. Then, it soaks the insulation, and can eventually leak through the ceiling drywall and into the home’s living space.
Preventing ice dams is relatively simple, and essentially comes down to improving insulation and ventilation, and removing heat sources from the attic. You should ensure you have the proper amount of insulation in the attic floor to keep heat from the living space from leaking into the attic and warming it. Of course, you should also keep your gutters clean. Before the snow falls, give your gutters a pre-winter cleaning, and check that your downspouts are properly functioning.
Proper ventilation is important as well. Proper ventilation will help prevent the attic from getting warmer than desired. Often during a home inspection we will observe soffit vents that get blocked by new insulation thus greatly lowering the ventilation. Lack of ventilation also makes it easier for condensation to build up in the attic which is easy to do when the underside of the roof is cold.
If, despite all your best efforts, you find you have an ice dam forming, you have a couple of options. As stated earlier, ice dams are worsened or sparked by heavy snow because snow is very insulating. You can use a roof rake to remove at least four feet of snow from the lower portion of the roof edge, and that can help prevent the ice dam from forming. Do not get onto the roof to remove snow. Another option you have is to apply calcium chloride or another ice melt product to the ice. If all else fails, or you simply don’t have the time or will to wrestle with the ice, you can always hire a professional ice dam removal company to take care of it for you. Do not hire a contractor that uses a high-pressure power washer with a steam box, as it can damage your shingles. Keep all this in mind, and you’re ready to take on the winter!
Written by Kaitlyn Troth of Troth Media