In the particularly cold months, “ice damming” can become a problem.
It starts out with cold weather outside, and insufficient insulation in the attic. The heat in the house escapes through the attic and melts the snow on the roof.
You have seen houses in subdivisions with no snow on their rooftops. Well, they weren’t just lucky! The snow melted.
If that was all there was to it, that would be the end of it: just money flying out through the roof. But, as nightfall sets in, the warm snow that melted throughout the day freezes. It backs up, just where it gets caught at the eavestrough. So, if there is some debris in the eaves, this point will melt and refreeze day after day at the right temperatures.
What you will see from the ground is large icicles hanging from the eavestrough. However, with the weight of the ice, it may pull the eaves away from the shingles and the roof. This is now a major problem.
Water can now run under the snow, down the rooftop, get trapped by the ice dam, roll over the side of the roof and down the wall, oftentimes, the inside of the wall. Here, you might experience freezing, thawing and refreezing. All of this causes damage to the building. If it reaches the ground which would be a good thing, there is also the risk that it could run down the side of the basement, and leak into the house.
In the Spring, it’s easy to repair. The eavestrough pulled away slightly from the roof, so nail it back in place. But, the real damage could be hidden behind the walls, or in the basement.
And, try to avoid the problem next year by increasing the insulation in the attic. Better safe, than sorry.
Brian Madigan LL.B., Broker