Hurricane Windows or Impact Windows are a product that have become prevalent over the past 25 years. Born in the aftermath of Hurricane Andrew, municipalities led by Miami-Dade in South Florida, saw the need for stronger window systems. Studies showed that if you were able to keep the exterior envelope intake during the storms (hurricanes), you have a greater chance of keeping the roof on the building in place and lessen the damage that could be created. To do this, the window industry didn’t have to go far to find a solution.
For years, the automotive industry had been using laminated glass for the windows in vehicles. Laminated glass is a type of safety glass that holds together when impacted with an object. In the event of breaking, it is held in place by an interlayer, typically of polyvinyl butyral (PVB) or ethylene-vinyl acetate (EVA), between its two or more layers of glass. The interlayer keeps the layers of glass bonded even when broken, and its high strength prevents the glass from breaking up into large sharp pieces. This produces a characteristic "spider web" cracking pattern when the impact is not enough to completely pierce the glass. Unlike the automotive industry, the window industry is trying reduce the shards of glass from flying, as well keep the window intact and not fail or “blow out” of the building.
Depending on the location, size of the panels, and design pressures, the interlayer used in the laminate may be of different thicknesses or types. For example, a .060-in PVB interlayer is a typical thickness and type of interlayer for Level C glazed areas. Other stiffer, more structural, interlayers, in thicknesses of .090, provide better resistance to tearing when subjected to Level D impacts at higher design pressures. The strength and other properties of laminated glass can be tailored to meet specific needs. The driving force behind the type of protection you are “required” to have is based on the geographic location of your home. These requirements are based on the local municipality building codes.
The State of Florida has been the driving force behind the development and implementation of building codes regarding hurricanes. After Andrew, Miami-Dade led the way with stricter codes for windows. In 2001, the rest of the state adopted the 2001 Florida Building Code standards. Since that time, several versions have come about. Florida is currently under the 2014 FBC standards. Taking Florida’s lead, other states in hurricane-affected areas began looking at their standards. Shortly after Florida rolled out its codes, states like Alabama, Mississippi, and Louisiana adopted the International Building Code or IBC. States like South Carolina and North Carolina followed as well. Texas developed the Texas Department of Insurance (TDI) for its protocols. All of these standards are designed to give a uniform standard to test and grade impact windows for safety and reliability to withstand hurricane-force winds and flying debris. But the term hurricane windows is a little misleading.
The benefits of these windows exceeds just those homes located in areas prone to hurricanes. Impact windows increase safety, noise reduction, and intrusion resistance. Burglars run once they try to smash one of these windows and realize that it is not going anywhere. Parents are not nervous when their small children play around a large picture window. And homeowners marvel just how much of the outside world’s noise no longer enters into the home. Impact windows are a great way to help reduce damage from severe thunderstorms that can have damaging wind. These types of storms can hit anywhere at any time. There is no replacing the peace of mind that a homeowner with impact windows goes to bed with.
As building designs and styles continue to evolve, many new features will come and go in the market place. One product that’s here to stay is impact windows. Their ability to add safety to any home provides you with more than just a return on investment. It provides you with the assurance that you have taken measures to protect your family and property from whatever life throws at you. For these reason, impact windows are an investment that all homeowners should evaluate.