Extreme winter weather can make conditions more than just cold and slippery. When snow and ice accumulate, it can become heavy and cause building damage or water damage.
Snow and ice can collapse roofs, especially on older buildings. Older buildings have a greater risk of corrosion, which can weaken its structural integrity. Newer buildings that have roofs made of light-weight metal, roofs that are flat, or roofs that do not have a lot of supports are more likely to give-in under the pressure of excess snow and ice. Snow drifts on a flat roof that have projections, a lower roof, or other equipment can accumulate snow that has drifted with the wind. This can cause vulnerability unless additional strengthening supports are added. One should contact a professional about safely removing excess snow and ice from a roof.
To help keep ice of roofs that are sloped, make sure attics are well ventilated so the snow on the roof does not melt and turn to ice. Melted snow and ice can enter a roof via the eaves and flat roofs can experience water damage if ice dams form and prevent water from flowing into drains on a roof.
Snow that builds up on walls and windows can cause water damage if it melts and leaks in through improperly sealed windows or into the basement. Basement drains, window wells, outside walls, and gutters need to be clear of any object that could cause them to clog.
10-12 inches of fresh snow or 3-5 inches of old or packed snow equal 1 inch of water and 5 lbs. of pressure for every square foot on a roof. Preventative building maintenance is crucial during the winter months to help avoid costly repairs.
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