Property losses from hurricanes and other natural disasters are on the rise, due to more weather events and higher rebuilding costs. In fact, 9 of the top 10 costliest storms in the U.S., led by Hurricane's Katrina's $108 billion in estimated damages, have all occurred since 2000, joining 1992's Hurricane Andrew.
Resiliency has become the new buzzword in the green building movement, with definitions ranging from off-grid energy independence to improved structural durability.
The Insurance Institute for Business & Home Safety (IBHS), a non-profit advocacy group for hazard-resistant construction practices, is out to define the term for building codes and federal legislation while promoting better building practices.
To make its case, IBHS engineers simulate certain high-wind events with full-scale buildings against current and upgraded residential building code standards at the Institute’s research facility in Richburg, S.C.
Next spring, for instance, IBHS will dial up a hailstorm—using real hailstones—to test impact-resistant siding and roof shingles and “provide a visual, real-world demonstration of common versus uncommon practices and products,” says IBHS spokesperson Joe King.
Earlier simulations, meanwhile, gave credence to the effectiveness of a continuous load path against wind uplift forces. IBHS now advocates upgraded, 7/16-inch roof deck thickness, 2 3/8-inch ring-shank nails, and a peel-and-stick roof membrane over the deck—ideally continuous or at least bridging the seams between panels—as a code-plus practice. “It’s not necessarily new technology, but it is definitely a new way of doing things for a lot of builders and framers,” says King.
Field investigations in storm-damaged areas supplement the controlled research to provide real-world examples of poor and preferred practices. In New Orleans following Hurricane Katrina, for instance, investigators found roof decks stapled to the structural frame, a provision long since removed from the code—and a glaring example of lax enforcement and old construction habits dying hard. Only a few homes in the path of Hurricane Charley in 2004, meanwhile, suffered structural roof failures, a testament to upgraded Florida codes against high-wind events.
In addition to lobbying for specific language and performance or prescriptive standards regarding durability and structural resiliency in future editions of the I-codes, IBHS is actively advocating federal legislation (specifically House bill HR 2069, the so-called Safe Building Code Incentive Act) to incentivize states to adopt and enforce the 2009 or 2012 IRC in order to gain an additional 4% federal disaster assistance funding.
Testifying before a congressional subcommittee on the proposed law last month, IBHS president and CEO Julie Rochman said the legislation is “a vehicle that puts scientific knowledge about the proven benefits of building codes to work, which will significantly improve our nation’s safety and resilience.”
The institute also lobbies state legislators to mandate insurance companies to offer discounted premiums for new and remodeled homes that meet the IBHS’ code-plus Fortified for Safer Living program, a voluntary, independently verified set of standards that reflects best practices for wind-event durability. In 2011, North Carolina and Alabama passed laws to that effect, and IBHS has its sight set on 16 other coastal states to follow suit.
For more information, including a recent analysis of building codes in 18 coastal states and the Fortified program, go to www.disastersafety.org.
Read a Case Study of a home certified to the Fortified for Safer Living program.