THIN IS IN: Designer fire-rated framing enters the market
Reprinted from Glass Digest
By Jerry Razwick, Technical Glass Products
"Keeping up with the Joneses." That phrase has come to characterize the American consumer who wants to do everything possible to have all the material possessions that the neighbors have.
It has also come to characterize manufacturers. If Dodge introduces a new feature on a minivan, you can be sure that Ford and Toyota will do their best to come up with an even better version of the feature. The public has benefited greatly from the concept of businesses "keeping up," since it has resulted in many outstanding new developments. The glazing industry is no exception to that pattern, yet as will be shown, sometimes one segment of the industry outpaces others.
Over the last two decades, the glazing industry has witnessed a revolution in the specialty field of fire-rated glass. What was once the domain of a single product (wired glass) quickly became a sophisticated and diversified array of product choices. Newer materials introduced the option of "wireless" fire-rated glass that offered additional benefits and capabilities.
Such a scenario is not uncommon. Items in many categories are regularly replaced by new-and-improved products. That is the nature of innovation. However, what has happened in fire-rated glass represents much more than simply an evolving product category. Instead, there has been a dramatic shift in thinking about fire-rated glass and how it is used.
For example, when wired glass was the only product able to meet fire codes, the codes were the driving force in the decision about what glass to use. Typically, no one would "voluntarily" choose wired glass without it being dictated as necessary for fire safety. After all, the wires don't particularly enhance the view through the glass. Wired glass is also broken fairly easily, leaving dangerous snags that can cause extensive injury.
However, since it was the only material that could satisfy fire requirements, architects and designers were left with little choice but to use it.
As new fire-rated choices entered the market, an interesting transition took place. Suddenly, there were products that looked like ordinary window glass and didn't need wires. What's more, these new products could actually surpass the performance of wired glass in fire testing. They also offered larger sizes, substantially better impact safety, thermal insulation and a range of aesthetic choices such as beveled edges, etched surfaces and a variety of textures.
The effect of all this development was to put the architects back in the driver's seat. Now, rather than simply resigning themselves to accepting a single product because codes demand it, design professionals can look at an individual project and consider all the needs - both aesthetic and functional - before specifying a particular product. Today, fire-rated glass can accommodate nearly any design without compromising safety or appearances.
Who would have thought 20 years ago that fire-rated glass products would be able to offer sound reduction? Who would have predicted insulated units with fire-rated ceramic on one side and one-way mirrors on the other? Clearly, the wide array of new materials has overturned many old concepts of the limits of fire-rated glass.
During this period of rapid innovation, the framing for fire-rated glass remained relatively static (at least in the North American market). Although new glass products were regularly introduced, not much thought was being given to the framing. As a result, fire-rated framing choices were typically limited to hollow metal steel. In other words, the framing simply wasn't "keeping up."
Much like wired glass, traditional hollow metal steel framing is able to get the job done, but not always in an aesthetically pleasing way. While functional, the bulky, wrap-around style of the frames is not always the first choice for appearance. Yet fire codes insist that frames must carry the same fire ratings as the glass they hold, so the number of available options has been restricted.
Fortunately, that is beginning to change, and framing is entering a new era. European style doors and frames have now been tested to North American standards. These new narrow profile steel doors and frames offer a strikingly different look than traditional hollow metal steel.
The difference is easily recognizable and is due largely to the method of manufacturing. Typical hollow metal steel framing is formed by bending sheets of steel. A standard 45 minute rated "wrap-around" hollow metal window has a profile of about 3" x 6".
The European style fire-rated framing is formed from steel tubes (instead of sheets) which are given shape in an extrusion-like process. Snap-on beads are used to hold the glass in place. The end product is extremely strong, and is only about 3" x 3" for a 45 minute rated frame.
What's more, the framing system is installed inside the fire-rated opening (much like aluminum store front systems) instead of wrapping around it. As you can see, this gives a much cleaner, sleeker appearance than has previously been available.
There are two different categories of the European style doors and frames. One category offers fire ratings of up to 45 minutes. These design-oriented doors and frames are intended to be used with standard thickness fire-rated products such as wired glass, Fireglass20 and the FireLite family of products.
The second category of doors and frames offers ratings up to 2 hours and the added benefit of being a barrier to heat. A special, solid insulating material is inserted inside the steel profiles to provide the heat protection. Transparent wall units such as Pilkington Pyrostop can be installed in these frames, making it possible to have floor-to-ceiling glass and full lite doors in 2 hour corridors (quite a contrast to previous limits of 100 square inch vision lites in 90 minute doors). Such large expanses of glass have not been conceivable in the past. Many architects have been literally stunned to learn about what is now possible.
European style framing usually comes finish painted and ready to install. Simple installation is one more benefit to these newer systems. For example, a glazier in California recently installed a 12' x 9' wall of fire-rated glass lites using the heat barrier framing. Based on his previous experience with other framing systems, he anticipated that the project would take him 12 hours to install. Instead, he had the project completed in just two hours.
Just as there was a shift in thinking about fire-rated glass, a shift is happening for fire-rated framing systems as well. Again, that change is moving from code-driven requirements to a focus on design and performance. Given the strength of the steel and
the narrow sightlines, it is now quite conceivable that an architect could specify the new European style fire-rated frames throughout a project - even in areas that are not fire-rated. Such an idea would have seemed far-fetched with traditional hollow metal steel framing.
With framing manufacturers starting to catch up to their counterparts in the fire-rated glass industry, a new trend is beginning to emerge in which glass and framing are offered together as complete system packages. Glaziers can do "one-stop-shopping" rather than hunt for separate suppliers for frames and glass. The advantages of convenience and assurance of compatibility make this trend likely to continue.
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