Last week's snowstorm in various sections of the state resulted in at least one roof collapse on a pig barn in southern Minnesota due to the accumulation of snow and ice.
Residential roofs can also sustain damage from the snow load.
For example, ice dams can form after heavy snowfalls followed by near-freezing temperatures. Snow melts down the roof slope and refreezes near the edge. Melt water builds up behind the ice dam and seeps into the home damaging drywall, carpeting and sometimes even collapsing ceilings.
In homes, the key to preventing ice dams is to keep the attic as close to the outside temperature as possible. Insulating the attic floor can accomplish this, and roof vents allow warm air to escape from the attic. Soffit vent allow cold air to enter the attic.
Sometimes the only option is to remove snow from the roof. Clearing the bottom six feet allow water to reach the drains and drain to the ground.
A person standing on the ground can use a roof rake to pull off snow.
A press release issued by Larry Jacobson and Kevin Janni, professors and agricultural engineers with University of Minnesota Extension, noted that on agricultural buildings, removing snow from a roof requires physically getting up on the roof and pushing the snow off with a shovel or broom. They said it's important to use ladders, safety ropes and take necessary precautions. When using a snow rake, be careful near overhead electrical power lines. Also, avoid excessive scraping on the roof or trying to chip off ice. These practices can damage the roof and lead to a leaky roof.