New Heights in Safety

Florida Building Codes, Post-Hurricane Andrew, Considered Model for the Nation

Now up in our Impact Series, we’ll cover a different type of impact—that caused by hurricanes and tropical storms. The bad news is that it’s peak season for hurricanes; the good news is that post-Hurricane Andrew (1992), Florida building codes were continually upgraded to new heights. Now, Florida building codes are considered by the Insurance Institute for Building and Home Safety to be a model for the rest of the nation—and we look to those stringent measures in our DLP Capital developments, both multifamily and single-family, so that our communities may stand the test of time. In fact, Florida’s stringent building codes are typically adopted, in some fashion, up and down the East Coast in areas subject to tropical storms, including in the Carolinas. But even when it comes to inland locations, Florida codes often influence building techniques, even sometimes adapted for seismic risks.

 Continuous Load Path

At the core of the new generation of building codes is what’s called having a “continuous load path.” Hurricanes like Andrew especially showed us the destruction that occurs with roofs uplifted and torn off by catastrophic winds. Now, to mitigate the risk of wind “uplift,” it’s standard to have a roof connected in a continuous path from the walls down to the concrete slab of a foundation. Think of it as the foot bone connected to the knee bone, the knee bone connected to the thigh bone…on up to the head bone. At the very foot of this continuous load path is typically a threaded rod system that is embedded into the concrete of a foundation. The walls are erected upon those rods and reinforced with rods at each floor, connecting to the trusses and roof to resist wind uplift. “This standard has been a game-changer,” said Garret Askew, Managing Director of Construction at DLP Capital. “It’s integral for best protecting the communities that we develop.”

New Heights in Safety

Ever see a roofer in your neighborhood laying out what looks like rows of tar paper for a new roof? This too, became standard in the years following Andrew. These rows are leak-barriers against wind-driven rain and are usually in the form of a material called “peel-and-stick” (like the adhesive for wall hooks). If roof shingles come off in high winds, the barrier is intended to protect the roof’s seal against water intrusion.

Wind Labs Test Resiliency vs. Airborne Objects

Likewise, windows and doors need barriers—against both water and wind. Multifamily and single-family homes typically have a building “wrap” material that protects walls and windows from water intrusion, especially if the siding on a building’s facade comes loose in high winds. If a home is within a mile of the coast in a hurricane-prone area, Florida Building Code also requires residences to either have hurricane shutters or windows that are impact-resistant up to 140 mph wind speeds. The resiliency of a window is tested in wind labs where 2x4s are propelled out of enormous air cannons—straight at a window to determine its vulnerability to high-velocity airborne objects.

Stilted Views?

And all of those homes you might see on stilts along coastal highways: Are they on stilts to enhance the views? Surely that’s a side benefit, but in reality the homes must be at least one-foot above the designated flood-elevation to limit the impact of rain and waves—so that homeowners might enjoy their sea views for generations to come.
 

In short, there were more than 400 different building codes in Florida before Hurricane Andrew. Now there’s one. We’ve covered some of its more basic elements in this feature. Sums up Garret Askew,