Wind Lbs On Roof

If your roof is located in windswept areas or even north of the treeline the wind will cause snow drifting making less of it accumulate on your roof.

Wind lbs on roof.

Slipperiness of the roof. The upward movement of the wind exerts an uplift load on the roof and the roof must be able to resist this uplift. In order for a structure to be sound and secure the foundation roof and walls must be strong and wind resistant. Wind exerts three types of forces on a structure.

When building a structure it is important to calculate wind load to ensure that the structure can withstand high winds especially if the building is located in an area known for inclement weather. Wind pressure is given by the equation p 0 00256 x v2 where v is the speed of the wind in miles per hour mph. Let s assume that the calculations for our building require a roof that can withstand 23 pounds per square foot of uplift force in the field of the roof. As you might expect buildings of high importance such.

For example if the wind speed is 70 mph the wind pressure is 0 00256 x 70 2 12 5 psf. A typical uplift load limit assumes a maximum wind speed of about 90 miles per. Wind flow under a roof pushes upward. Wind flow over a roof pulls upward.

The unit for wind pressure is pounds per square foot psf. Because fm approvals requires a 2 1 safety factor roofs with field of roof uplift forces of 30 pounds per square foot are the maximum for 1 60 ratings and 37 5 pounds per square foot are the.