Reeling from more than a decade of powerful hurricanes dating to
the devastation caused by Hurricane Andrew in 1992, Florida enacted
the nation's toughest building rules in 2007. Among them was a
requirement that self-adhering underlayment be installed with all
new and replacement steep-slope roof systems.
Some of those rules were revised in 2008, including a rule that
makes self-adhering underlayment optional rather than mandatory. As
could be expected, there was an initial surge in demand for
self-adhering underlayment following the initial rule's passage,
but what is surprising is the continued strong demand after the
rule was modified.
Specifically, Section 201.2 of Rule 9B-3.0475 (Hurricane
Mitigation Retrofits For Existing Site-Built Single Family
Residential Structures) describes options for a "roof secondary
water barrier for site-built single family residential
structures."
Adopted by the Florida Building Commission in October 2007, the
rule was quite stringent, mandating that roofing contractors either
cover all joints with a minimum 4-inch-wide strip of self-adhering
polymer-modified bitumen tape applied directly to sheathing or
decks or cover entire roof decks with approved self-adhering
polymer-modified bitumen cap sheets. The rule was relaxed in March
2008 to allow other options, including covering the entire roof
deck with "an approved asphalt impregnated 30# felt underlayment
installed with nails and tin-tabs as required for the HVHZ" with no
additional...
Log in or register for FREE access to this article and other Professional Roofing online content.