by Mark Schleifstein
Staff writer

Requiring that new structures be designed to survive Category 3 and stronger hurricane winds would save lives as well as buildings, and in the long run would save homeowners money.

Jefferson Parish officials found a disturbing flaw last year in their plans to open "refuges of last resort" for people stranded in a major hurricane: Only a few interior areas in a handful of public buildings could be trusted to withstand the 155- to 200-mph winds of a Category 5 storm.

"We were not really surprised," said Louisiana State University Hurricane Center director Marc Levitan, who oversaw an engineering assessment of the parish buildings. "Even in Florida, with their much more strict building codes, they’ve had serious problems with a deficit in safe shelter space."

New Orleans authorities decided to abandon similar refuge plans after concluding that up to 90 percent of the buildings in the city are vulnerable to damage from the most powerful hurricanes. Jefferson Parish is moving forward cautiously, knowing space will be limited for those left behind.

Emergency officials in both parishes say they are hoping to persuade people to evacuate rather than end up huddled in buildings that might dissolve or explode in the teeth of nature’s most powerful force.

"We just don’t have the structures in the metro area that are constructed to take that kind of wind," Jefferson Parish Office of Emergency Preparedness director Walter Maestri said. "Our building codes have not required us to build buildings capable of withstanding 170- to 200-mph winds, and engineers are now saying there may be even higher winds. Here the standard is 100 mph. And of course a lot of our buildings, except for the newer buildings along Poydras Street (in New Orleans), were built prior to any code being in place at all."

But experts say that must change: As Florida upgraded its building code and strengthened enforcement after Hurricane Andrew in 1992 and California has long required buildings designed to survive major earthquakes, south Louisiana needs to make changes to protect property and provide basic shelter for those caught in the path of a killer storm.

"We at least ought to be looking at hardening (making buildings more resistant to high winds) as far as public buildings are concerned," said Hucky Purpera, chief of the natural and technical hazards division in the Louisiana Office of Emergency Preparedness. "Every high school that’s built could become a shelter, or certainly a refuge of last resort to save lives."

Authorities say protection could be greatly improved with some basic changes, including design and construction practices that would add as little as $2,000 to the cost of a new home or to retrofitting an existing one.

"For wind damage, it’s relatively inexpensive to do these things, like hurricane clips and straps on beams and rafters to hold roofs on," Purpera said.

Legislative requirements

Next year the Southeast Louisiana Hurricane Task Force, which comprises city and parish emergency preparedness directors, will recommend that the Legislature consider requiring any new government buildings built south of Interstates 10 and 12 to be constructed to withstand the worst of hurricanes.

"They should be built to withstand a Category 5 hurricane, not only wind load, but from an elevation standpoint for storm surge," said Gerald Falgoust, director of the St. James Parish Office of Emergency Preparedness and former chairman of the task force committee that is recommending the strengthened building requirement. "There are things that can be done if some engineering takes place prior to a building being built."

The problems with structures considered as last-resort refuges in Jefferson Parish included wide expanses of glass that would allow wind to "blow up" a building if debris smashed through the windows, walls built without reinforcing bars necessary to withstand 150-mph to 175-mph winds, and roof beams that were too long to guarantee they wouldn’t collapse in such winds, LSU’s Levitan said.

In many cases, water damage to roofs and walls also made the buildings too vulnerable to the effects of winds, he said.

The state-approved building code used in Jefferson Parish requires buildings to withstand the effects of winds blowing at 100 mph for three minutes. That’s the equivalent of a shorter gust of wind blowing at 120 mph. A Category 3 hurricane can be accompanied by sustained winds of 130 mph and much stronger gusts.

Falgoust said the Legislature shouldn’t stop with strengthening requirements for public buildings. Building codes in the state should also be strengthened to reduce damage to private homes and businesses from such storms, he said.

Purpera agreed, saying California’s building code has been strengthened several times during the past 20 years as officials learned more about how to protect buildings from the effects of earthquakes.

"We’re way behind that, as far as preparing for a hurricane in Louisiana," Purpera said. "Architects aren’t aware of what it takes to harden homes or buildings to withstand hurricanes in New Orleans, how to create a lot of individual refuges that could save lives."

Steven Bassett, a Palm Beach, Fla., mechanical engineer who helped Florida officials in their 10-year effort to rewrite the state’s building code to address problems revealed by Hurricane Andrew, said strengthening the code will result in significant savings.

"States with substantial coastal regions should consider following Florida’s lead," Bassett said. "To do so will improve building and housing integrity, save money through reduced storm-related property destruction and better protect the health and safety of those states’ residents and visitors."

Florida’s new code, and an even stronger code in Miami-Dade County, requires buildings on the beachfront to withstand sustained winds of 150 mph. Wind-speed requirements drop for buildings farther inland.

A preliminary study by Florida building officials of three large, expensive new homes found that the new state code added 3 percent to 10 percent to the cost, depending on whether the structures were built with masonry or wood, as well as the types of materials used to protect windows and other wall openings.

Levitan said such increased costs might be offset by lower insurance and repair costs over the life of the building.

"People think of building codes as a stick, but there’s also a carrot coming with them," he said. "With a more strict building code, you might be able to get insurance, or pay less for it, or have a smaller deductible if the house is built to a better standard. Wind is the biggest single catastrophic loss that the insurance industry has to pay off," because flood damage is covered by the federal National Flood Insurance Program.

Improvements in building codes and their enforcement also can reduce the cost of flood insurance, as seen this year when a good code-enforcement record resulted in a 5 percent across-the-board reduction in flood insurance rates for New Orleans homeowners.

New Orleans is moving toward adopting the International Building Code and International Residential Code, which will require new buildings to withstand the effects of a 130-mph wind gust blowing for three seconds, a 10-mph improvement over the state’s existing code.

Though the code requirements would seem to indicate a building would have to withstand the effects of a strong Category 3 hurricane, that assumption is inaccurate. Wind speeds in the Saffir-Simpson scale used to categorize hurricanes are based on one-minute averages, not gusts. Gusts can be as much as 50 mph stronger than the maximum sustained wind speeds, experts say.

During Hurricane Betsy and an unnamed 1947 hurricane, officials measured 125-mph sustained winds in New Orleans. The highest sustained winds measured in New Orleans reached 130 mph during a 1915 hurricane. Those winds ripped the steeples off a dozen churches and damaged thousands of other buildings in the city.

New Orleans also has the unique problem of protecting the centuries-old buildings in the French Quarter, which are both historic and a major tourist attraction.

Louisiana State Museum director James Sefcik, who manages many of the oldest buildings in the city, including the 18th century Cabildo and the Presbytere, said he is not too worried about damage from even the worst hurricanes.

"I don’t have any doubts our buildings will take any level of hurricane," Sefcik said. "After the (1988) Cabildo fire, we instructed our architect to put the building back the way it was before. If you look at the Cabildo and the Presbytere, those cypress beams are about 14 inches thick, and they are pegged together, so it’s unlikely anything is going to happen."

In advance of Hurricane Georges, he said, his staff boarded up the buildings in eight hours.

"We also can remove from the ground floor of buildings any artifacts that we feel would be at risk from rising waters in a day or day and a half," he said.

However, he is not so sure about other buildings in the Quarter. "I think that if their roofs are in bad repair, they’re probably going to go. I think flying debris is probably going to be a serious problem. Lesser buildings, a lot of them are going to be damaged."

‘Roofing was a problem’

Along Biscayne Bay in Miami-Dade County, by contrast, the building code required structures to be built to withstand winds of 150 mph even before Andrew. In interior parts of the state, the standard is 120 mph.

Still, thousands of buildings in south Florida were severely damaged or destroyed by Andrew’s 135- to 145-mph winds.

Investigations after the storm found that much of the damage was the result of faulty construction and poor code enforcement.

"Roofing was a problem," said Bill delGrosso, emergency management coordinator for Miami-Dade County. "It had been installed with nail guns, and now we require screws. It’s simple survivability things like that that really caused an awful lot of damage during Andrew, simply attaching roofs correctly."

But the biggest problem centered on the Miami-Dade County code’s lack of a requirement to cover window openings, Bassett said.

Homes with windows that were not protected by shutters or shatter-resistant window glazing were supposed to be designed to withstand the pressure of high winds pouring into the structure. But they weren’t, he said. Today all buildings in Miami-Dade County must be built with shutters or windows designed to withstand windblown debris. Coverings made of 5Ú8-inch plywood also are acceptable.

Miami-Dade County, using a Federal Emergency Management Agency grant, also is installing shutters on several thousand homes owned by low-income residents, part of the county’s strategy to have residents upgrade buildings to the point that they don’t have to go to storm shelters.

The proposed changes in New Orleans’ building code will require windows to be made of impact-resistant glass or to be protected by shutters, or that buildings withstand a 130-mph gust with or without window coverings. But adoption of the new code would not require retrofitting of older buildings. Building code administrator Curtis Mann said state law prohibits the city from applying codes retroactively unless more than 50 percent of the structure is being replaced.

Mark Schleifstein can be reached at (504) 826-3327 or mschleifstein@timespicayune.com.