How Do You Calculate Roof Snow Loads?
Whether you are building an accessory structure in the backyard or trying to decide whether you need to shovel off your roof after a storm, you need a way to learn whether your roof materials are up to the weight–expressed as psf, or pounds per square foot–of the snowfall in your area. This pressure is increased or decreased based on the pitch of the roof. You can compute real-time snow load for quick decision-making or use official figures to design a new building. Push the ruler or yardstick into the snow horizontally in a spot that is representative of the overall snow depth and record the depth in inches. Convert your depth measurement to a figure expressed in feet. For instance, using a snow depth of 15 inches: 15 divided by 12 (the number of inches in a foot) yields 1.25 feet. Collect a cubic foot of the snow on the ground, choosing a sample that is representative of the overall snow pack, and weigh it. Snow may range in weight from 7 up to 20 pounds per square foot, depending
