What can you do if your building has excessive snow depth?
The simple answer is to get the deepest snow off as soon as possible. Generally, one has some time between a large snowfall event and possible structural failure.
Before beginning removing snow or even entering a building with excessive snow on the roof, look for indications of building damage and the beginning of failure. Look at the sidewalls to see if there are any bulges or indications that knee braces have failed. Look at the roof line to see if it is still straight. When entering a building with excessive snow, look at the ceiling, open trusses and walls for indications of damage or failure. If there are indications of building damage or failure, do not climb onto the roof or enter the building while the snow is on the roof.
One way to remove snow from a roof is to physically get up on the roof and shovel off the snow. There obviously is a human safety concern of falling off the roof when working on a snow-covered and icy roof. One should use ladders, safety ropes and take necessary precautions. Hire a professional if possible.
Other alternatives are to use snow rakes or specialty tools that can be used from the ground or from portable scaffolding. When using a snow rake or specialty tools, use extreme caution when working near overhead electrical power lines. Also, avoid excessive scraping on the roof or trying to chip off the ice. These practices can damage the roof and lead to a leaky roof.
There are other methods of removing snow and ice from roofs. If the weather is not too cold, hot water or some other heat source can be used to melt snow and ice. Another method involves warming the inside of the building sufficiently with large heaters to melt the ice layer and then waiting for the snow and ice to slide off. Obviously, a lot of heat is necessary for even a moderately-sized building, and the building must be an open-trussed structure (no flat ceiling) and have an uninsulated metal roof. Caution is necessary to prevent large chunks of ice and snow that slide off the roof from falling on people, animals or equipment. Putting heaters in an attic of buildings with flat ceilings is not recommended because of the fire and carbon monoxide danger and the possibility of creating ice dams along the building's eaves.
It is difficult to say how much snow or ice is safe because it depends on the building design and the snow or ice weight. In most cases, agricultural buildings will have an excessive snow load if there are more than four to six feet of snow on the roof.
Excessive snow and ice followed with cold temperatures can create excessive snow loads. You should monitor the snow load situation on your agricultural buildings and take appropriate action. Check high risks areas and if you need to remove snow please be extremely careful.