Hurricane windows. Impact products. Dade County-approved windows. You’ve probably heard at least some of these terms, especially if you live in an area where violent weather is the norm. But what is a hurricane product, really? And how can windows become considered “impact windows”? Perhaps this brief explanation will help you make a more informed decision if you’re researching impact protection.

First, you have to realize that for windows to be considered hurricane or impact products, they need to be impact tested. This testing determines if the windows and laminated glass used in them can withstand violent weather. Laminated glass will crack and shatter, yes, but nothing should ever actually get through the glass and into your home. It’s not easy to have windows pass impact testing. It’s a long, difficult process.

“Standard” window impact testing means that a window with clear, double-pane glass is tested for air, water and structural requirements (per AAMA standards). Three other units— ones with laminated glass—are tested with hits at different places on the window from a single missile (which is actually an eight-foot 2 x 4 weighing about nine pounds) traveling at about 35 mph. Every window tested for impact is also tested with various cyclic wind pressures, both inward and outward (9,000 total cycles). After all this—assuming a window passes—it’s considered Level “D” hurricane protection. That means it’s approved for use in homes up to a mile inland from the coast.

So if that’s “standard” hurricane impact window testing…what’s special about “Dade County” hurricane protection products? The difference is this: the Dade unit that’s tested for air, water and structural requirements is also made with laminated glass—and is subjected to longer sustained wind load testing. Plus, instead of being hit just once, the three laminated impact windows are “impacted” two to three times in several places. When—and if—a product can achieve Dade County approval, it can be used pretty much anywhere, even right on the coast and in Miami-Dade County, FL.