This instructional material has been prepared for those of you who think 40 degrees Fahrenheit is cold.
An ice dam typically forms at the edge of a roof when some of the snow in the roof melts and the water runs beneath the blanket of snow. Snow may melt even on very cold days if a roof has not been well insulated. The water trickles down toward the gutter as it does in warm weather. Often the gutter is filled with snow or blocked in some way creating slush. When the temperature goes back down, the slush freezes forming ice. Ice may also form when water moves past the heated part of a roof onto eaves that extend beyond the heated room below. When more water forms and drains down the slope of the roof it encounters the dam of ice formed previously and puddles up. The dam grows in size and more water collects behind it.
This puddled water can cause serious damage to a roof. It may seep under shingles and when it freezes pop the shingles up. It may find an opening through the shingles and drip into the house. Significant damage can occur if the problem is not addressed. It can be one of those pay me now or pay me later deals.
The photo shows the snow pack on our house. This situation developed from several heavy snows without wind. A warm day or two and the snow hardened up so that it would no longer blow off the building. If you look closely, you should be able to see the ice forming at the edge of the roof.
Sometimes homeowners purchase special aluminum rakes (snow rakes) that allow them to remove the snow along the edge of a roof. This becomes difficult to do when the snow hardens and not possible with a roof like ours which is 2 ½ stories in some sections. Someone has to go up there to get rid of the snow. This is a job for someone who knows what they are doing and who is significantly younger than me. The idea is to get rid of as much snow as possible and salt the ice dams so the ice melts. This is an expensive proposition – it takes some time and is difficult and dangerous work. Home ownership can involve such unexpected costs.
Happy New Year! My son calls this a “first world problem” and I agree.