Rain raises roof collapse risks after snowstorm
Property damage risks are rising today as rain begins to fall on snow-covered roofs following the snowstorm in the northeast. The weekend storm dumped as much as 40 inches of powder on properties New England. Add rain to that mix and this means the risk of roof collapses is heightened, cautions the Insurance Institute for Business & Home Safety (IBHS).
“If possible use a snow rake to try to remove what you can safely from the ground,” says Dr. Tim Reinhold, IBHS senior vice president for research and chief engineer. “Flat roofs are the biggest risk when it comes to snow and ice accumulations. These types of roofs also are the most difficult when it comes to clearing off the snow and they may not drain as well once the snow begins to melt. The best advice is to hire a contractor to clear the roof.”
How much snow is too much for your roof to handle?
If your roof is still covered following the snowstorm, use these IBHS guidelines for helping to determine how much weight could be bearing down on the roof.
Fresh snow: 10-12 in. of new snow is equal to one in. of water, or about 5 lbs per square foot of roof space, so you could have up to 4 ft. of new snow before the roof will become stressed.
Packed snow: 3-5 in. of old snow is equal to one inch of water, or about 5 lbs per square foot of roof space, so anything more than 2 ft. of old snow could be too much for your roof to handle.
Total accumulated weight: two ft. of old snow and two ft. of new snow could weigh as much as 60 lbs per square foot of roof space, which is beyond the typical snow load capacity of most roofs.
Ice: one in. of ice equals one ft. of fresh snow.
Find more advice for protecting your property against damage from severe winter weather at disastersafety.org/freezing_weather.
© 2012 Insurance Institute for Business & Home Safety