Florida’s newer roofs passed the Irma test
If you work hard to put a roof over your head, then you will want to listen to what Dave Roodvoets has to say.
With 35 years of experience studying hurricane damage, he is an expert on roofs, and, of special interest to Floridians, why they fail in windstorms.
Roodvoets is a leader of the Roofing Industry Council on Weather Issues (RICOWI), which sends teams to disaster areas so the damage may be inspected and the cause of failures determined. He has worked with the Florida Code Alliance and is a member of the RICOWI wind and hail investigation teams.
These teams were very busy during the historic 2004 hurricane season in Florida. Hurricane Charley in August of that year tore off many a roof with its 145 mph winds. Roofing codes were toughened after that.
RICOWI’s experts won’t go to just any hurricane. Harvey, at least in Houston, was a rainmaker, not a roof-remover. Other storms are more about surging water than howling wind. Or they might not have sustained winds of at least 95 mph in a developed area.
That, he says, is how it is turning out with Hurricane Irma. It scared the dickens out of most Floridians with its winds of up to 185 mph while it was out to sea. But once it hit the mainland of Florida, it lost a lot of wind power — although surge and rain did plenty of damage.
Roodvoets said the state’s roofs that were built to code — an increasingly higher percentage with each passing year — performed so well that they really weren’t put to the test.
Using high-resolution satellite imagery of Irma-affected areas from NOAA (it is available online), he sees that most of the wind damage was limited to trees, aluminum structures, older houses and power poles — and the tree damage was not that pronounced among palm trees.
“The palm trees along the coast looks pretty darn good,” he says. “That says we didn’t have really high winds. If a palm tree is hit by 130 mph winds, it would be laying on its side.
“The wind speeds (on the mainland) at ground level were not nearly as high as they (meterologists) were talking about, as best as we can tell.”
In the Sarasota area, winds topped out at about 80 mph.
Roodvoets and his colleagues saw damage “here and there,” probably among older houses, he said. “Our conclusion at this point is that the new building codes are really working. The roofs are staying on; the houses are not blowing over.”
As a result, RICOWI will not be sending a team to Southwest Florida.
The Florida Keys are a different story. He sees evidence of a tornado in the area between Marathon and Key West, as well as a devastating storm surge. A RICOWI team will go there.
“Because of the codes, and because the wind speeds really were not what was expected at ground level, Florida dodged a bullet,” he said.
“The contractors are doing good work in the state of Florida, building these places to code,” said Roodvoets, who added that the new codes have not really been tested. “You also have great code officials. The people who wrote the code worked hard at it.”
Also, Roodvoets agrees “100 percent” with the statement that new buildings, elevated above the base-flood elevation and with better roofs, windows, doors and walls, are surviving weather challenges a lot better than infrastructure.
“The power companies have to learn how to keep their poles up and trees off the wires.”
He advises consumers, when reroofing or building anew, to ask for materials and methods that exceed the local building code. In most of Sarasota County, the code requires new buildings to withstand 160 mph winds.
“Make sure the roofer knows that the materials meet or exceed the Florida code,” he said. “Shingles, tile, metal — most of the manufacturers have products that will meet the code. If it were my house, I would go with a metal roof that is screwed down. They have some other problems, but they probably would not blow off, in most cases.”
Materials are important, but installation is critical.
“Always make sure the contractor has installed such roofs before,” he said. “Ask for his credentials, how long has he been in business in the state of Florida. What do you know about designing for wind? The good contractors have people who know about this stuff. Florida now has some very good contractors. That is the good news about Florida right now.
“This hurricane was at least a test, if not the ultimate test.”
Original article shared from - www.heraldtribune.com