Fire-rated choices for school applications

“I’ve replaced my school district’s broken wired glass for many years. Now, administrators say I need to retrofit all their schools with fire-rated glass that meets impact safety codes. What options can I provide, and what issues should I be aware of?”

The 2003 International Building Code forever changed the rules about the use of wired glass in schools. Contract glaziers and glass-shop owners in many parts of the country only now realize the true impact of that change as more jurisdictions adopt the revised code. After decades as the standard choice for fire-rated openings in educational facilities, code officials no longer allow traditional wired glass in hazardous locations including doors, side lites and openings near the floor. That eliminates many of the applications where it was once the only acceptable glazing material.

At first glance, the rule change may seem arbitrary. Why curtail use of a product with such a lengthy track record of fire protection? The answer lies in how it handles human impact.

Most people on the street view wired glass as security glazing. Unfortunately, the mesh in wired glass does very little to enhance its impact safety. The glass only has about one-quarter the strength of tempered glass in terms of impact resistance.

When the U.S. Consumer Product Safety Commission first developed impact standards for glass in the mid-1970s, wired glass presented a dilemma. It couldn’t meet the impact requirements, but it was the only glazing material available that offered fire protection. There was no alternative that combined fire and impact safety in a single product. Faced with an either-or choice, officials determined that the overriding concern was fire protection. So they granted wired glass a temporary exemption from meeting the impact requirements of CPSC 16CFR1201. That temporary exemption remained in place for nearly 30 years, resulting in the widespread use of wired glass in locations that would normally require true impact safety glass. During that time, the number of injuries due to broken wired glass grew.

Meanwhile, manufacturers introduced newer glazing products without wire mesh that surpassed wired glass in every category of performance. With a range of safer alternatives and the ongoing threat posed by broken wired glass, the International Code Council decided during the 2003 IBC revisions that it was time to lift the exemption. Now, the IBC requires all glazing in hazardous locations in grades kindergarten through 12, as well as athletic facilities and daycare centers, to meet CPSC impact safety standards.

Where does that leave you, the glazier? You face a number of alternatives to traditional wired glass. Fire-rated glass ceramic is a natural alternative. It is cuttable, it’s available in large sizes and it fits in the same frames as wired glass. It also is available with high-impact safety ratings, making it an ideal choice for school.

One of the most recent introductions in the market is a 20-minute rated glazing material that is annealed glass, not tempered. That means it can be cut by distributors rather than by the manufacturer, shortening lead times and allowing it to be stocked locally.
Newer generations of wired glass have also begun to emerge. Manufacturers have developed a laminated version of wired glass that meets CPSC 16CFR1201, Category I. It is permanently labeled as required by the IBC, and makes for an affordable solution.
Another wired glass utilizes a fire-rated surface-applied film to achieve higher impact safety. However, in school settings, filmed products may incur marring, scratching and peeling, thereby affecting the products’ ability to perform. As distributors of a filmed product, we generally recommend that other alternatives be chosen for educational facilities to avoid the film abuse and possible need for repeated replacements.

Selection criteria
While no single product will be right for every application, the following questions can help you narrow down your choices to those best suited for your project:
•   Will the glass be in a high contact environment?
•   If there will be a great deal of pedestrian traffic near the glass, you may want to avoid filmed products. The potential for maintenance problems may offset any initial cost savings the glass has to offer.
•   If the glass needs replacing, will it need to happen quickly?
•   If you’re in the replacement business, you probably have a good idea of the openings most likely to need frequent repairs. Do you have the luxury of a long lead time or will you need to install something right away? In schools, the answer is almost always “as fast as possible.” Look for products that can be stocked, cut to size and permanently labeled by local distributors, rather than at the factory, to meet building code requirements.
•   Does the product I’ve chosen to replace traditional wired glass meet all the requirements?

Not all fire-rated glazing options are equal. Make sure the one you’ve chosen arrives properly labeled, carries a sufficiently high fire rating, satisfies the impact safety requirements and is being used with a proper sealant. Don’t forget to check the rating on the framing as well. The entire system needs to be compatible for the fire rating to be valid.