Bulked-Up Windows Draw
Buyers in Hurricane Areas

Residents and building inspectors in hurricane-prone areas increasingly are counting on extra-strength windows to help batten down the hatches for storms.

Typically made using plastic film that is sandwiched between two pieces of regular glass, impact-resistant panes are tempered to add strength and then fitted into durable, heavy-duty aluminum or vinyl frames.

In Florida, impact-resistant glass must endure testing aimed at simulating hurricane conditions, such as firing concrete chunks and pellets at the glass. PGT Inc., a Venice, Fla., maker of residential impact-resistant windows and doors, says the "impact test" for its windows includes a nine-pound, two-by-four piece of lumber that repeatedly hits the glass at a speed of 50 feet per second.

Much of the higher demand for PGT and other manufacturers is the result of tighter building codes, rather than voluntary consumer foresight. In 2004, Florida ordered the use of impact-resistant products in buildings seen as vulnerable to wind speeds of more than 110 miles per hour or 120 mph, depending on location. Miami-Dade and Broward counties require at least some extra window protection on most new construction and remodeling projects.

The stronger windows and other window protections can make a difference. When Hurricane Wilma hit South Florida in October, the storm blew out windows in buildings erected before the building codes were tightened. In contrast, buildings with impact-resistant windows generally suffered little damage, says Michael Ashworth, manager of the modular-buildings program at the Florida Department of Community Affairs, a state agency.

Windows offering extra protection from hurricanes cost two to three times as much as conventional windows, or roughly $275 for a 24-inch-by-30-inch storm-resistant window and $1,000 for a 48-inch-by-72-inch version. A cheaper alternative can be sealing the window glass with press-on film. This type of reinforcement, which is allowed under building codes, has been catching on with builders and consumers as well.

Steve Sabac, owner of Sun Coast Glass Protection Inc., which manufactures see-through window film attached to window frames on major buildings, says the two brutal hurricane seasons in Florida have increased the company's volume to 25 to 30 buildings a year, up from about four a year in 2003 and earlier.

Should a window break during a storm, "the film prevents it from spreading everywhere and killing people," Mr. Sabac says.

Even bulked-up windows aren't always ready to take on Mother Nature. Some of the major buildings along Miami's Brickell Avenue took a beating from Wilma. At both the Four Seasons Hotel & Tower, a 70-story building that opened in 2003, and the 36-story Espirito Santo Plaza glass tower, which have hundreds of extra-strength windows, damage was extensive. While most of the damage was slight cracks, some windows broke completely, says Joe Ferras, a Miami city-government building official.

About half the damaged windows at the luxury Conrad Miami hotel, part of the Espirito Santo Plaza, still need to be fixed, says Robert Thrailkill, the hotel's general manager. But he says the impact-resistant glass did its job well overall because the inside of the hotel received very little damage.

Tim Reinhold, vice president of engineering at the Institute for Business and Home Safety, a Tampa, Fla., engineering and research group that includes insurers and reinsurers, says the window failures during Wilma show that standards for impact-resistant windows need to be toughened.

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