TECHNICAL NOTICE
May 19, 2008

PRESCRIPTIVE CORNER AND PERIMETER OPTIONS FOR FM 1-90 RATED SYSTEMS*

FM Global (FM) Property Loss Prevention Data Sheet 1-29 (DS 1-29) was revised in August, 2007 to provide prescriptive approaches for enhanced fastening in perimeter and corner areas for roof systems that require up to and including 1-90 rated systems in hurricane prone and non-hurricane prone areas.

In non-hurricane prone regions, FM requires an increase in the number of fasteners per board in corner and perimeter areas over the FM Approved field-of-roof fastener spacing. Details are provided in section 2.2.1.5.1 of DS 1-29.

For hurricane prone areas where a Class 1-90 rated system is needed for the field of the roof, there are two generic assemblies provided in DS 1-29 for use in the corner and perimeter areas to provide acceptable wind resistance in those areas. In hurricane prone regions, TAMKO allows use of either DS 1-29 prescriptive corner and perimeter option in conjunction with TAMKO 1-90 rated systems to provide a Class 1-90 rated roof installation.

A copy of DS 1-29 is available at roofnav.com. Additional information about TAMKO products is available at www.tamko.com.