With winter comes the chance of blizzards, which can cause damage to a roof that is not prepared to handle the weight of snow. Knowing your roof’s weight limit and taking simple maintenance steps before a storm can prevent damage and protect your home and family.
Blowing and drifting snow common during a blizzard can cause uneven distribution of snow, which can weaken a section of the roof. Less snow accumulates on a steep roof. The greater the angle of a roof, the more weight it can handle. A flat roof in good condition can handle about two feet of snow. Most angled roofs can support 20 pounds per square foot of snow. Homes built in areas prone to heavy snow may have been constructed to handle more than that amount of weight.
One foot of new snow weighs approximately five pounds per square foot, so most roofs can handle up to four feet of fresh snow. Old, packed snow three to five inches deep is equivalent to one foot of fresh snow. An inch of ice is equal in weight to a foot of fresh snow, so your roof can support the weight of up to four inches of snow.
Prior to a blizzard, check your roof for loose slates or shingles. If you are unsure if your roof can support the weight of a large amount of snow, have a contractor inspect it and make any necessary repairs. During or after the storm, clear snow from the roof using a snow rake, rather than climbing onto the roof.
A little maintenance and preparation can prevent serious damage to your home in the event of a blizzard. Now is the time to inspect your roof, before the threat of a blizzard is imminent.