Textiles are applied to revolutionize the capacity of hurricane protection systems.
By Sonja Hegman
The hurricane barrier/protection industry started about 50 years ago. Initially, only wood planks were used to board up windows, and the more well-to-do homeowner used wood shutters with iron clasps to keep out the elements. “Now, wood shutters are commonly used for decoration,” says Dennis Grubb, founder of Wave Guide Technologies in Jacksonville, Fla.
As technology marched forward, aluminum became the popular choice for protection, Grubb said, but it was cumbersome and expensive. Aluminum was generally used as a manual shutter that had to be closed using a fastener. Eventually, aluminum was replaced with roll down products [that were] originally developed and used in Europe, Grubb says. “They were used to control heat loss or heat gain. In World War II, roll downs were used as security.”
The roll-down technology was brought to the U.S. about 20 years ago, and it was developed and sold—in either motorized or manual form—as a hurricane protection product. But, Grubb says, these products were still expensive. “About five years ago, I decided that needed to change,” he said.
So Grubb developed a product that was more affordable and easier to deploy that used industrial fabrics: the Clearlar system, which is designed to custom fit to the window using an aluminum mounting system that works manually or motorized. Made from an industrial/military grade of super reinforced polymer-based fabric, Clearlar is coated with multiple layers of an ultraviolet- and mildew-resistant PVC coating material. It is certified by the National Accreditation & Management Institute Inc. for installation in any hurricane prone area, as it complies with the state of Florida’s hurricane protection building codes. When tested by the state of Florida, Grubb claims that Clearlar withstood winds of 330km/hr; it’s guaranteed up to wind speeds of 282km/hr by Grubb’s company. “It has never failed me on a test,” he says.
Fending off flying debris
Though Dr. Patrick Hook’s company doesn’t manufacture products specifically for hurricane protection, Auxetix Ltd. has developed preventive fabrics that stretch and can contain flying debris. As managing director of the company in Witheridge, Devon, England, U.K., Hook played a part in creating ZetixTM blast-mitigation fabrics designed to be used in any environment where it is necessary to ameliorate the effects of high-pressure blasts. These blasts could arise from terrorist strikes, mineshaft disasters, or natural events such as hurricanes or typhoons.
The fabrics are made from fibers composed of elastomeric cores around which high-strength fibers have been helically-wrapped. When these fibers are stretched, they deform into a spiral shape, according to Hook. This causes a large number of pores to open up across the fabric’s surface when the material is stretched. The creation of extra surface area in this manner also makes the material thicker and wider.
The working principle is that the Zetix materials are anchored above and below a window or other opening that needs protection. When a blast front hits the material, it stretches into a curved shape. “This opens the pores and allows the blast to pass through without damaging the fabric,” Hook says. Any flying debris, however, is caught by the high-strength wrapping fibers. “This is extremely significant, as it is airborne fragments of glass and metal that cause 80–90% of deaths and serious injuries in a blast-related event.”
One of the most important factors with the Zetix fabrics, however, is that they are multiple-use materials—conventional blast-films and safety curtains no longer provide any protection once they have been deployed, Hook notes.
Tests performed by the British government involving large quantities of high explosives have shown that an excellent degree of protection is provided by Zetix fabrics, Hook says.
“The tests were done using large quantities of high explosives which showed an excellent degree of protection,” he explains. “They continue to provide this protection, even after being subjected to substantial blasts. Consequently, they would provide excellent defenses for buildings in hurricane zones where sustained protection is necessary.”
Rolling right along
Amy Berckman is starting to see more fabric than she has in the past. As co-owner of Coastal Awnings and Hurricane Shutters in Morehead City, N.C., Berckman says hurricane protection was always a part of her business plan. She’s following in Grubb’s footsteps by offering fabric-based high wind and hurricane protection. Her company offers fabric barriers made out of a trampoline-type material, and has for the past seven years. A combination of fabric and roll shutter might be used, based upon the customer’s request.
Although North Carolina’s coastline is prone to hurricane activity, the awareness of different products isn’t always obvious, she observes.
“If people don’t see [hurricane protection products], they don’t know there are options,” she says.
Caribbean Awning Production Co. Ltd. manufactures two types of shutters for hurricane protection. In 1998, the company expanded its operations from awnings to indoor treatments and hurricane/security shutters, says Paula Calderon, managing director of the St. Lucia-based firm. The company has spent large amounts of money promoting and educating the general public in the Eastern Caribbean about hurricane shutters over the past nine years.
Calderon recommends rolling shutters and accordion shutters. “While we can offer storm panels and bahama shutters, we do not feel that these are as practical as the rolling and accordion shutters,” she explains. Rolling shutters are designed to allow the blade to roll up inside its hood capacity. The result is a clean and attractive look, an important consideration for a home’s or business’ exterior appearance.
Aluminium slats are filled with either foam or extra hard resin—or extruded aluminium for tougher applications. The blades are vented to allow in air and light. The shutters can be motorized with a manual override system in the event of power failure.
Accordion shutters are manually operated. Every shutter comes with its own high-security locking device, “a sure nuisance to any prowler as well,” Calderon says. “After hurricane Ivan hit the island of Grenada, there was a sudden hunger for hurricane/security shutters, both for the protection of homes and businesses and the security against looting,” Calderon adds. This brought a wider appreciation and understanding of the products her company provides.
For Larry Batz, manager of Awnair Adjustable Awnings in Belleview, Fla., hurricane barriers became a necessary product for his company three years ago. Before that, Awnair sold only awnings.
Awnair sells three main panels as hurricane protectors: clear, aluminum and steel. Like Caribbean Awning, Batz sells roll-down shutters, accordion shutters (that are permanently mounted on a building, in clear or aluminum), and storm shutters (that look primarily like decorative shutters). Ease of use is important because the many retirees that live in the area need to be able to deploy the products—or make it easy for a neighbor to do so.
When Hurricane Charley hit in 2004, Batz says that it didn’t affect his area of Florida much because it’s in the middle of the state; but Hurricane Frances, which hit that same year, knocked out power to Batz’s business for nine days.
So far this year, hurricane barriers have accounted for 30 to 40 percent of Batz’s sales, compared to last year’s 20%. “A lot of it has to do with the storm season,” Batz said. “Last year we had only one [tropical] storm.”
Amy Berckman also says that a “significant percentage” of her company’s sales come from hurricane barriers. Awnings and blinds represented Caribbean Awning’s largest earnings until Hurricane Ivan in 2004, Calderon says. After that, sales of shutters increased from 22–63% in 2006, with 32% representing exports to the other Caribbean islands.
Caribbean Awning’s greatest profits are generated from the awnings and blinds industry, Calderon adds. The shutter industry poses problems with the different styles of homes built in the islands—the poor construction of houses; the lack of understanding of the products and their uses, and the discrepancy of the architects’ fancy designs with the practical aspects of building for the use and installation of shutters.
“Customers have to make a choice between the fancy architecture and the protection of property, family and business,” Calderon says. “The lack of education about these shutters in the region among architects, contractors and builders, as well as banks and insurance companies, is hindering the protection of homes.”
Banks and insurance companies, she observes, should encourage the placement of shutters in homes because the shutters protect their investments. “Shutters should be incorporated in the design of buildings, and this is far from the case in the region,” she says.
With the change in weather patterns and the prediction of increased hurricane activity over the next 10 years, it is important for professionals in the building industry to re-examine the way homes are constructed and designed, Calderon says, “taking into full consideration the customers’ needs.”