As the snow comes down over Wisconsin, you’ll want to watch how many inches accumulate on your agriculture building roofs. Any obstructions, such as ventilation or a cupola, or changes in roof height or pitch, are places where snow can really pile up. Heavy snow loads can result in roof collapse or damage.
Prevent loss with proper maintenance
Inspect buildings before winter
David Bohnhoff, an emeritus professor at UW-Madison’s Department of Biological Systems Engineering, says you’ll want to inspect your building for wood decay or metal corrosion. If you’ve damaged a support post with a piece of machinery, for example, or have corrosion of metal truss plates, that can be an issue once you’ve got the weight of snow up above. If you see a problem, get it repaired right away.
Pole buildings that were exposed to collapse conditions last year but somehow stayed up are now at a greater risk of collapse. When a pole building carries a load at, near or above the snow load rating for an extended period of time, the Gusset Plates, Bottom Chords and Webs weaken, often permanently. Most agriculture buildings are rated to 38 pounds per foot when built; some of these (because of the loads from last year) may now only hold 28 pounds before they collapse.
Remove snow from the roof
Once snow is on the roof, there’s a few ways you can get it off.
- It’s recommended to use a snow rake with a long extension arm to remove snow while standing safely on the ground. It isn’t recommend to walk on the roof for snow removal. This can not only damage the roof, but be very dangerous on the snow and ice covered surface.
- You can also get the roof to shed the snow itself. This works in an animal confinement facility. You can drive up the roof temperature by warming up the building and closing the ventilation system. Once the building is above the freezing point of the snow, it will start to melt against the building’s roof. That water will cause sheets of snow to slide off.
- However, as the snow melts, that water will run down to the eve and freeze. That frozen ice will create an ice dam, preventing snow from sliding off. Make sure you remove that ice as the snow melts as ice dams can cause water backup resulting in damage.
Ice damming is a well-known and well documented condition. Property owners should be aware and realize that it’s their responsibility to maintain their properties to prevent such conditions. Taking preventative measures can help reduce damage from occurring and minimize repair costs. It’s important to review your insurance policy with your agent to educate yourself on coverage specific to your policy.
Watch for snow drifts
High winds can cause snow to drift as high as the roof. If you see this happening, get your loaders out and move those drifts before it climbs onto the roof and becomes additional weight.
Wisconsin is seeing bigger snow falls – and more rain – at one time. This is happening because air fronts are moving at a slower pace as a result of climate change and the temperature extremes from one area of the country to another.
Structural engineers are accounting for these issues today in their building designs, but older buildings are not designed for it. Check with your insurance agent that your farm buildings are properly protected.
