Tech Today

Concerns with FM 1-52 testing

FM Global recommends performing field uplift testing as a quality-assurance measure on most membrane roof systems in hurricane-prone regions of the U.S. NRCA has concerns about whether FM Global's test method provides an accurate prediction of quality installation and actual uplift performance.

For buildings located in hurricane-prone regions where the design wind speed is 100 mph or greater, FM Global recommends to its insurers that acceptance of and final payment for most new membrane roof systems be based on satisfactory completion of a field uplift test. In the U.S., this recommendation applies along the Atlantic and Gulf coasts and in American Samoa, Guam, Hawaii, Puerto Rico and the U.S. Virgin Islands.

The FM test

FM Global recommends such testing be conducted according to Loss Prevention Data Sheet 1-52 (FM 1-52), "Field Uplift Tests." FM 1-52 provides two methods of testing membrane roof systems: bonded uplift and negative pressure.