Uplift Characteristics Of Metal Roof

To recommend practices for designing and installing metal roof systems that will enhance wind resistance in high wind regions i e greater than 90 miles per hour mph gust design wind speed.

Uplift characteristics of metal roof. These two types of metal roofs exposed fastened and standing seam i e. Let s take a look at how wind uplift from extreme weather affects roofing and examine the engineering behind the superior wind protection of decra metal roofing. Wind uplift ratings wind zones and specific wind uplift requirements. Defining wind uplift wind uplift is created when the air pressure below the roofing system is higher than the air pressure above the roof.

These tests are necessary to understand how a metal roof. If you have a vertical column and footing that support only 100 s f i would use c c wind load roof uplift on that column and footing despite the fact that the column receives the wind load through roofing insulation boards screws attaching the boards metal deck joists beams bolts connecting beams etc. Numerous factors ultimately determine the severity of the suction pressure. Current wind uplift tests and how they are performed.

Specific metal roof products panel profiles and applications that perform best for wind uplift. Under the same weather condition a single block of metal roof suffers a wind uplift equivalent to a uniform load. Fm 4471 astm e 1592 ul 580 or ul 1897. The control equations can be solved by external constraints and applied loads.

Metal roof systems in high wind regions april 2009 page 1 of 5 purpose. 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. To ensure a correctly built metal roof there are a variety of wind uplift tests manufacturers use to test their metal panel systems. Wind design is complicated and calculating the correct roof design parameters is challenging.

Panel width and profile metal type and thickness clip type and frequency type and number of fasteners and the roof deck contribute to the uplift resistance of every metal panel roof system. 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. The wind clamp an extruded piece of aluminum that is placed on the panel seams at clip locations is one accessory that can be used to improve wind uplift characteristics on metal roofs delivering substantial time and cost savings as these devices help mitigate risk of wind uplift and improve overall wind design. Therefore the entire metal roof can be seen as a rectangular plate with two opposed simply supported edges and two other free opposed edges.

Concealed fastened have different performance characteristics when exposed to high winds.