Too much snow on a roof can cause problems, according to Tom Blackmore, Jamestown city building inspector.
Snow loads on roofs recently caused two buildings in the Fargo area to collapse, according to a reports by The Forum of Fargo-Moorhead.
"I think this is a good time be cognizant of all the snow we've had," Blackmore said. "Whether to remove the snow or not should be decided on a case-by-case basis."
Snow removal from roofs appears to be on the minds of area residents.
"Sold out of roof rakes," said Bill Walsh, a clerk at Mac's, on Monday afternoon. "Last Friday we had seven or eight on hand."
A new supply isn't likely to come in until next week.
Building codes require roofs to be able to carry a weight of 40 pounds per square foot, Blackmore said. There is no particular snow depth that would reach that weight.
"We have varying types of snow," he said. "The roof could be covered with light, fluffy snow or heavy, wet snow."
Blackmore said if a person decides to remove the snow, he or she needs to be careful. Using a roof rake from the ground eliminates the possibility of the person falling from the roof but creates a danger of damaging the roof.
"You don't need to remove it (snow) all the way to the shingles," Blackmore said. "That could damage the roof surface."
Going on the roof and shoveling the snow clear have their own set of dangers including falls and slips on icy roof surfaces.
Contractors are expecting more calls to clear snow from roofs, according to Dave Steck of Steck's Handy Man.
"One person has called so far," he said. "It was wet, heavy snow. Lot of work."
The type of home and its location also play a part in snow accumulations. Homes with flat roofs or roofs with low slopes commonly accumulate more snow. A house in a sheltered area will also end up with more snow on the roof than a home in the open where the wind blows most of the snow clear.
Removing the snow near the edges of the roof can also prevent ice dams.
Ice dams occur when the snow melts higher on the roof and then freezes at the edge of the roof. If this forms a ridge of ice it can prevent more water from running off the roof and result in leakage.
Blackmore said homeowners should always think safety when dealing with a roof.
"Have somebody outside with you when you do it," he said. "Or hire a contractor."