Laminated glass was patented in 1909 and entered the mass market as a life safety product. In the late 1920s, laminated windshields became a common safety feature for vehicles, saving countless lives. It then became a critical material for building security and protection. Fueled by the terrible destruction from hurricanes during the 1990s, laminated glass became mandatory for structures in storm-prone areas. And it grew into an important safety solution for man-made threats, from simple break-ins to more devastating bomb blasts. The building industry has looked beyond just the safety benefits of laminated glass to aesthetic and acoustic performance as well.
The strength and security of laminated products garnered the attention of architects, as they sought to push the envelope of what’s possible with glass. The last decade has seen exciting developments in everything from point-supported facades to glass stair treads to glass balustrades. Laminated glass is maximizing transparency, while ensuring safety and security. This envelope pushing has also opened the door for more “extreme” glass possibilities.
About two years ago, I was able to experience the extreme possibility of glass when I visited “The Ledge” in Chicago. I stood 1,353 feet above the ground in an all-glass box cantilevered 4.3 feet from the Willis Tower. It was incredible. I experienced some of the thrill of skydiving, base-jumping or hang gliding (all extreme activities that I will likely never attempt), but with complete confidence in my own safety.
From “The Ledge,” I looked between my feet toward the grid of streets far below, where cars appeared as moving specks of light. My heart raced and my stomach dropped. But, through the adrenaline, the still-rational part of my brain continued to assure me that the three layers of laminated glass under my feet, on all three walls of the box, and above my head, were more than enough protection.
Glass has become a favorite material for these safe, but extreme, applications, such as the Grand Canyon Skywalk, where visitors can stand 70 feet from the rim of the Grand Canyon at the, 2,000 feet in the air. At the Zhangjiajie National Forest Park, tourists can walk 4,700 feet above the ground along a 200-foot skywalk that traces a sheer cliff-face of Tianmen Mountain. Starting in June, visitors to the new the U.S. Bank Tower in Los Angeles will be able to pay $8 to slide down the glass enclosed 45-foot Skyslide running from the 70th floor to the 69th floor.
We highlighted several extreme glass applications in the May issue of Glass Magazine, including the impressive Glacier Skywalk in Alberta, Canada, featured on the cover, China’s Zhangjiajie Grand Canyon Glass Bridge, and the and Tilt! in Chicago (pp. 38-44). This issue also provided an important look at another type of safety glass, capable of handling extreme situations—fire-rated glass. On page 14, view an updated guide to fire-rated glass codes and standards.