With snow piling up on my roof I am afraid it might do damage or worse yet cave in. What can I do?
Lisa – Ypsilanti, MI
I have talked to many people with the same concern this week. The fact is, snow along with ice could cause roof damage. The threat of collapse is a very low probability, but possible. As I stated in my February 10th, 2010 article “preventing Ice Dams”, sometimes snow can weigh up to 30 LB per square foot. On a 1500-square-foot house with a roof surface area of 1600 square feet, that’s 48,000 Lbs or more on your roof! Some roofs aren’t built to withstand that amount of weight. The weight of a large amount of snow and ice can also cause damage to your gutters and downspouts.
The damage mostly occurs when the snow melts and refreezes underneath snow where it meets the shingles. Snow melts due to the heat from the attic, then drains to the gutters and refreezes. Now the water and ice accumulates and works back up the roof growing underneath the shingles causing damage – and in many cases melts into the house.
Using a roof rake will help you alleviate some of the stress on both you and your roof. A roof rake is a solid piece of metal or plastic about 16 to 20 inches wide on the end of an extension pole which allows you to “rake” or pull snow off the roof. They can be purchased at most of your local hardware stores. Remove as much snow as possible from the top of the roof down toward the gutters. About 10 to 15 feet should be sufficient. Never remove the snow while on top of the roof. For obvious reasons, it is a slippery slope and snow isn’t as soft as you think to land in.
Apply calcium chloride to all ice in gutters and down spouts. Do not use sodium chloride (rock salt), or table salt, it can cause damage to your landscape greenery. I’ve seen homeowners insert calcium chloride into panty hose and lay it inside the gutters, it was successful to remove the ice. To apply, I recommend tossing it up into the gutters, sounds funny but it really is the best way.
There is controversy over whether or not to use a ladder when removing the snow. I believe it is much safer not to use a ladder because when the ice and snow melts, it can accumulate on the rungs of the ladder and refreeze in minutes. This is definitely a slippery and hazardous situation. You can easily fall and get seriously hurt.
Lastly, if your home continually has a problem with ice damming, have a professional check your home for proper roof ventilation and insulation. You may consider having heat tape installed in those problem areas along your roof then you’d be able to melt the ice with a flick of a switch. Heat tape is a low temp electrical cord that is normally placed along the perimeter of the roof, in the roof valleys and in the gutters and downspouts to keep the water moving during the frigid winter months. It should be installed by a professional.