It’s bound to happen: a seasonal news story – or many – about a commercial roof collapsing because of the weight of several inches of recently fallen snow. The collapse isn’t the result of a failure of the roof, but the structure beneath it that couldn’t hold up to the additional weight of the snow. It may seem insignificant, but a square foot of heavy snow six inches deep can weigh 10 pounds. For just a small 1000-square-foot roof, that’s five tons of extra weight. Most flat commercial roofs are, of course much larger than that, and if yours is aging with weak areas, heavy wet snow could be a recipe for disaster.
If you have accumulated snow on your commercial roof, it might be a good idea to get up on it (safely – more about that below) and clear some or all of it away.
With respect to appropriate tools, a snow rake is better than a shovel, because it’s less likely to damage the surface. If shovels are all you have, make sure they have plastic (not metal) edges, and leave a couple of inches of snow on the roof. Scraping it to the surface could damage the roof membrane.
Also make sure that drains, gutters, and downspouts are clear. Over the course of a winter, your roof is likely to undergo multiple freeze-and-thaw cycles, and snowmelt needs a place to go. If your drainage system can’t handle it, you’re likely to get layers of ice building up on your roof – and that can be even heavier and more dangerous than snow.
During your rooftop snow removal operation, practice good safety behavior. This means being extra cautious around the roof’s perimeter and near skylights. An inherently unsafe situation in clear, dry weather becomes downright hazardous in snowy, windy, wintry conditions.
If you’re not comfortable taking care of this yourself, hire a professional. Contact Great Lakes Roofing to discuss our full range of commercial roofing services. We look forward to hearing from you!