Wind Uplift On Flat Roofs

When there is no wind the air pressure on the upper surface of a roof system is the same as that on the underside.

Wind uplift on flat roofs.

The effects of wind uplift on roofs. This test determines the uplift resistance of roof assemblies consisting of the roof deck and roof covering materials by evaluating the comparative resistance of roof assemblies to positive and negative pressures. Wind load calculations for flat roofs are of paramount. 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.

The present study demonstrates the pressure variations due to wind load on the pyramidal roof of a square plan low rise building with 15 wall openings through cfd computational fluid dynamics simulation. When opting for a polymeric single ply membrane roofing solution one of the key documents is the wind uplift calculation and not just for mechanically fastened roofs they can be just as important for adhered roofs when in certain locations or possibly with a higher risk of exposure. 1 3 3 roof design wind loads. Roof shape and slope are both important parameters for the safety of a structure especially when facing wind loads.

Many studies on roofed structures have been performed in the past. Omg roofing products conducts a wind uplift test on a 12 foot by 24 foot section of a system at its dedicated testing facility in agawam mass. This exerts a significant amount up pressure against the structure and pushes air upwards. In order for a structure to be sound and secure the foundation roof and walls must be strong and wind resistant.

Bauder technical department can provide wind load calculations on request in accordance with the uk national annex to eurocode 1 actions on structures part 1 4. Then in 1992 hurricane andrew pounded south florida like few storms ever before. General actions wind actions bs en 1991 1 4. This includes structural components such as roof sheathing or rafters or roof cover components and the connections of these elements.

In 1989 hurricane hugo ripped through the carolinas leaving miles of devastation in its wake. Ul 580 is the standard for tests for uplift resistance of roof assemblies. Roof design wind loads are the wind pressures and resulting uplift forces for which the roof structure is designed. The video below was posted on linkedin recently by a technician for roofing contractor in the us.

What we are seeing here is a fairly extreme case of wind up lift on a flat roof which will cause significant damage to the membrane.