Perhaps the best way to compare the differences in design wind pressures derived from FM 1-28, ASCE 7-05 and ASCE 7-10 is by example. FM Global's Property Loss Prevention Data Sheet 1-28, "Wind Design" (FM 1-28), includes the following example design wind pressure determination.

A manufacturing building is located in New Orleans. The building is an enclosed structure with a low-slope roof system and a roof height of 33 feet. The building is located in an area categorized as Exposure Category C.

The resulting design wind pressures are shown in the figure.

FM 1-28 and FM Global's other roofing-related Loss Prevention Data Sheets are accessible at www.fmglobaldatasheets.com and in the Reference Materials section of www.roofnav.com.

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