This Gold Mountain Single Truss Arch Storage Shelter W30’xL40’xH15′ is made in a durable frame – galvanized steel tubes, so it’s more stable and less shaky, can resist strong wind and crazy snow. It is an ideal choice for the all-season outdoor storage shed. The durable UV-resistant canopy is in PE Polyethylene fabric and protects your belongings from sunshine and water. The rollup door is easy to put down and roll up on windy or rainy days to add one more protection. The 304015R heavy-duty canopy storage shelter is for industrial, commercial, agricultural applications, and you can also use it for warehouse, storage tent, garden and lawn equipment, backyard items, firewood, vehicle shed, etc. It’s necessary to tighten the roof fabric enough to avoid ”hammocks” on the roof and also re-tighten once or twice again after a few months of use. This is important when assembly in cold weather autumn and winter because the fabric is stiff then and when we got the sun and warm weather afterward it will make the fabric ”slack” again and need to be re-tighten before next winter.It’s the owners’ responsibility to take off snow immediately if not slide off by itself.