code watch

High Wind Construction Standard
In the calm before the storms, development of ICC Standard on Hurricane Resistant construction begins.

by David Bowman, P.E.

The one-two punch of hurricanes Charley and Frances just three weeks apart drives home the point that Mother Nature still trumps mankind in her ability to wreak havoc with the built environment. The good news is the loss of life from the two hurricanes was minimal. The bad news is the property losses, though not as devastating as Hurricane Andrew in 1992, are still staggering.

Thankfully, improvements in Florida’s building codes lessened the potential damage. However, the impact of these storms underscores how important the need is for even stronger construction in hurricane-prone regions.

An effort under way by the International Code Council (ICC) fills just that need. The public safety organization is currently developing a standard to address special construction requirements for buildings in regions that historically experience high winds associated with hurricanes. Not only the coast of Florida is impacted by hurricanes; the entire Eastern seaboard from Florida to Maine as well as the Gulf Coast states (Texas, Louisiana, Mississippi and Alabama), are susceptible to high winds that place huge demands on buildings.

The purpose of the new standard, the ICC Standard on Hurricane Resistant Construction, will be to provide prescriptive regulations for construction of buildings in high-wind areas. Essentially, the prescriptive regulations provide a “user friendly” approach for homebuilders and builders of other small structures that would reduce the need for special engineering designs.

HIGH-WIND RESISTANCE
With a focus on high-wind resistance, the new standard will contain details for construction in regions where the three-second-gust wind speed equals or exceeds 110 mph, based upon a 50-year mean recurrence interval. The standard will provide guidelines for use in such regions to address structural elements that need to be more wind resistant, including:

• Additional roof deck hold down and stiffening
• Additional lateral support of the structure, using wood panels or heavy-duty bracing
• Additional roof membrane and shingle fastening requirements
• Additional reinforcement of masonry and concrete walls
• Additional framing connectors for roof framing hold down

The ICC Standard on Hurricane Resistant Construction is the descendent of the Standard for Hurricane Resistant Residential Construction, also known as SSTD 10, developed by the Southern Building Code Congress Inter-national (SBCCI). SBCCI was one of the nation’s three regional model code organizations that consolidated into the International Code Council to create one national model code organization.

CHALLENGING TASK
The ICC Consensus Committee on Hurricane Resistant Construc-tion is tasked with developing the new standard. Its challenge is to provide fundamental details that represent basic industry needs, and still allow for a reasonable amount of options in design and construction of a light-frame or small building in high-wind areas. The committee is made up of experts from all of the materials industries: concrete, masonry, wood and steel; engineers and architects with experience in wind design; and building officials. The committee’s goal is to develop a prescriptive standard that will improve wind resistance while keeping construction affordable in hurricane-prone areas.

The committee conducted its first meeting in July, in the relatively calm month preceding the staggering storms of Charley in August and Frances in September. (As this is being written, Ivan is heading toward the U.S. coastline. [Editor’s Note: as this issue goes to press, Ivan has looped around to confront Florida and the Gulf Coast a second time as Jeanne approaches from the east.]) During the meeting, the committee focused on organizing the group and defining the areas of technical work that would be needed. For information on this committee, please visit www.iccsafe.org/cs/standards and select the Hurricane Resistant Construction page, where the committee’s efforts are regularly posted.

The next meeting is scheduled for December 13 to 14 in Atlanta, GA. Watch for the announcement on our Web site in November. All meetings are open to the public.