Freezing temperatures, snowfall and a comparatively warmer attic provide all the ingredients for the formation of ice dams on roofs. If your home is located in an area that experiences this type of winter you, too, should be concerned with preventing ice dams before they form. Failure to do so results in long, heavy icicles hanging from the gutters, the potential for a hefty personal injury lawsuit filed on behalf of injured visitors or mail carriers, and of course the possibility for a damaged roof. While the novice might consider melting ice dams to be the only method for dealing with this occurrence, there are actually other ways of dispatching the problems. Better yet, the handywoman of the house might be able to do a quick fix in just one weekend day! (The long-term home repair will take a bit longer.)
Understand what causes ice damming on roofs. Before digging up the ice chipper and snow rake, become familiar with the phenomenon that involves melting ice, dams, snow and the roof line. In simplest terms, water from thawing snow and ice – located at the roof’s apex — builds up behind the still frozen ice around the eaves. Over night, this water freezes. The next day, when the household is in full swing, warm air leaks cause more melting and water runoff. Ice builds up and forces its way underneath shingles, in between gutters and the roof line, and also along drainage pipes.
As the water once again freezes over night, the ice begins to dislodge the shingles, gutters and so on. Leave the ice dams on roofs intact, and before long you are looking at a hefty roofer repair bill in spring or summer. The implication is clear: improper attic insulation allows for the thaw-and-freeze cycle to continue.
Rake the snow off the roof. This involves a ladder, snow rake, balance and a fearless demeanor. Unless you feel comfortable being about 10 feet up in the air, do not attempt to do this! Call out a professional instead.
Check the attic insulation. The University of Massachusetts points out that ice dams on roofs are a clear warning sign that all is not well with the attic’s insulation. The handywoman needs to get up into the attic and check for potential leaks around windows, skylights and vents. If there is dampness, investigate further and check for rotting wood in the attic space. Not a glamorous job to be sure, it is vital for the continued soundness of the roof structure.
Install a quick fix until spring. Preventing ice dams from forming can be as simple as temporarily installing 12-inch deep continuous R-38 ceiling insulation in the attic. Caulk around exhaust fans, hatches and ceiling lights. Seal off the area around the attic hatch with tape to limit hot air leaks that contribute to the heightened roof temperatures from the home’s living space.
Add soffit vents to the roof. When spring comes and it is time for a more permanent fix to the ice damming on roofs, soffit vents make a good investment. They maintain an attic temperature that is in keeping with the external air. Not surprisingly, these vents counteract even minute heat leaks and keep the roof sufficiently cool to prevent the thaw-and-freeze that leads to ice dams on roofs.
Melting ice dams may sound like a quick fix for the icicles that now hang from the gutters, but it does not really work. Oh sure, there is the heat tape that RV stores sell, but as anyone who has ever had the black water tank on an RV freeze during winter can tell you, this tape simply does not work well. Instead, carefully dislodge the icicles with ice chippers and prevent ice dams from forming in the first place.
University of Massachusetts: “Preventing Ice Dams”
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