Volume 29, Issue 1 - Spring 2015
Open the Floodgates
Fire-rated glass can be used in place of opaque building materials, helping provide a bright, light-filled space.
No matter how pretty, how attractive, how stylish or how clear, it’s still there because of a need—and a big one at that: life safety.
Parking garages can be visually opened up and made safer by using fire-rated glass.
Visibility is Key
Of course, glass allows for interior visibility, which is one of the greatest benefits it provides over opaque materials such as concrete. In settings such as schools and universities, which call for fire-rated surfaces, architects are able to meet this need by using glass, providing a bright, light-filled space. At the same time, the need for enhanced security has also increased. Fire-rated glass can be combined with other security features, resulting in a product that can pull double duty. Alice Dickerson is the marketing manager for AGC Glass Co. North America, which manufacturers Pyrosafe fire-rated glass. The glass is fabricated and distributed in the U.S. by Trulite Glass and Aluminum Solutions. Dickerson says schools, for example, need to maintain safety and security, but want to have visibility, allowing those inside to see what is happening. That glass, though, has to meet fire codes. The development and advancement of intumescent products, which eliminate the transfer of re-radiated heat, has made this possible.
Institutional facilities, such as schools, are common areas of application for fire-rated glazing, which can be combined with other security features.
“It used to be all you had was wired glass. Then there were ceramics, but they had poorer clarity. As fire-rated manufacturers continue to develop products, you’re getting clear, high-quality float glass—it looks like float glass,” says Dickerson, explaining the glass can now be integrated into many other products, such as an insulating glass unit, which could then be combined with a decorative product.
Peter Lindgren, president of Aluflam North America in Cerritos, Calif., agrees that the introduction of intumescent fire-rated glass has had a significant impact on the industry.
Fire-rated glazing is even being used in luxury homes where a fire separation is needed between the garage and the living space.
“The earlier wire glass products (as well as ceramic-type glass) provided virtually no resistance to heat transfer. In the case of a fire, the glass would block flame and smoke for the rated time, but would allow the heat from the fire to pass from one side to the other. In extreme scenarios, enough heat might transfer through and cause fire to ignite in combustible materials on the other side. For this reason, codes would allow only limited use of these types of [fire-protective] products,” he says. “In contrast, the intumescent fire-rated glass is built up of layers of glass and clear intumescent materials and offers superior resistance to heat transfer. Together with specially insulated framing, it became possible for the manufacturers to pass tests for fire resistance ratings (UL263/ASTM E119) for wall assemblies and temperature rise ratings (UL10C) for doors. This revolutionized the potential uses for fire-rated glazing systems.”
And Dickerson adds, “As [manufacturers] continue to advance, architects are not restricted to just one product, and there is more of a selection.
Grimshaw Architects and James Carpenter Design Associates incorporated fire-rated glazing supplied by Technical Glass Products into various parts of the Fulton Center in New York, including an elevator, helping provide compartmentation and drawing light in to maintain its light-filled aesthetic. Enclos was the contract glazier for the Fulton Center project, which was completed in 2014. It also features balanced doors from C.R. Laurence. Other suppliers included Viracon, providing the glass for the skylight and the curtainwall on the Broadway elevation; Saint-Gobain, providing glass parasols below the skylight; and Avic Sanxin, which provided the pavilion curtainwall glass.
Over Head, Under Foot, All Around
Botman explains that the increasing options in fire-rated glazing provide a means to use more glass, reducing the amount of, or even replacing altogether, other opaque fire-rated building materials.
“Look at all of these buildings with concrete walls and think about where you would [like to have transparency],” he says. “Where would an architect want to make an opening in these required separations in a way not thought of before? We (manufacturers and suppliers) have to help them [architects] see how what used to be a dark hole in a building can become an architectural feature. That opens up a broad range of where fire-rated glazing can be used.” This may start with a door, but that can evolve quickly to corridor windows and walls. Stairwells have also become a popular application.
“The whole stairwell itself could be made of glass to have visibility and light. Instead of being a concrete tunnel or tube, it can now be a glass feature,” says Botman, who’s quick to add, “We still have to convince the architect about having the light and visibility.”
Overhead glazing and flooring, as well as exterior glazing, are also opportunities to allow in more light. Technologies today now allow these products to be used in fire-rated applications.
“I think architects want to bring more light into the building, and many buildings are being built closer together,” says Art Byrd, inside sales manager with Vetrotech Saint-Gobain in Auburn, Wash. As a result, Byrd says they’re seeing a growing number of requests for exterior fire-rated applications. Consider, for example, property line requirements. Buildings in urban locations are being built closer together; as close to property lines as possible in some cases. According to the International Building Code, however, exterior walls that are 10 feet or fewer from the property line are required to have a fire-resistance rating based on the proximity to adjacent buildings and interior occupancy conditions. Fire-rated glazing can be used in these exterior applications, providing not only the desired aesthetics, but also required performance.
Byrd adds, “Architects want the exterior wall to be all glass, but they still have to protect the occupants.”
Devin Bowman, vice president of sales with Technical Glass Products in Snoqualmie, Wash., says systems also are available that allow for fire-rated glass in horizontal applications, such as floors and skylights.
“Areas where you have requirements for a fire-rating, but still want to allow natural light,” Bowman says. “There are also advances in glass curtainwall that has the appearance of being structurally glazed. This means you don’t have to have a cover cap on the exterior. Architects like as much glass as possible and little interruption, so it’s an attractive option for them.”
Without sufficient communication, the success of the fire-rated project can be at risk. Suppliers agree they spend countless hours talking with those in the architectural community about when, where and how to use these products.
“I think that [more and more] we’re communicating with architects and designers on what they’d like and are working with them to come up with a common solution for the [aesthetics] of what they are designing,” says Byrd. “Communication is the key in finding what they want and how we can assist them to get there.”
Ellen Rogers is the editorial director of Architects’ Guide to Glass & Metal.
Architects' Guide to Glass & Metal