Steel roof decks are common substrates for low-slope membrane
roof systems. Recent changes to recognized guidelines may affect
the design and installation of roof assemblies that include steel
In January, FM Global updated its Property Loss Prevention Data
Sheet 1-29, "Roof deck securement and above-deck roof components,"
and several changes affect steel roof decks.
FM Global requires steel roof decks approved by FM Approvals be
used for all insulated steel roof decks. In addition, deck spans,
which are measured center to center, should not be greater than a
deck's specific approval issued by FM Approvals. In some instances,
roof decks' allowable deck spans according to FM Approvals are less
Log in or register for FREE access to this article and other Professional Roofing online content.