Glass & Metals 401

An architect’s guide to protective glazing
Katy Devlin
April 30, 2013

Glass & Metals 401:


With security concerns on the rise in light of recent tragic events, the project scope for protective glazing is changing. What was once thought to be a specialty product reserved for high-risk buildings is increasingly finding its way into other nonresidential building segments.

“In the past, security glazing was defined more for banks, correctional facilities and military installations. There are more conversations on this topic now, related to school safety, but no clear trends or solutions yet,” says Walt Lutzke, marketing coordinator, Tubelite Inc. “Security is a topic that is not going to go away, especially for public buildings.”

In part four of Glass Magazine’s “All About Glass and Metals: A Guide for Architects and Specifiers” series, “Glass and Metals 401” examines the trends, applications and new product options for security glazing products (ballistic, bomb and burglary resistant). It also looks at fire-rated glazing, which is increasingly being asked to do double-duty in terms of fire and ballistic protection. In addition, the guide addresses common questions and specification mistakes associated with these types of products.

Security Glazing Trends

Top of mind in the protective glazing field is the use of security glass products in educational facilities.

“It seems Newtown was one of those ‘watershed events’ that changes not only the way people think, but also affects industries,” says Rod Van Buskirk, owner of glazing contractor Bacon & Van Buskirk, speaking of the Dec. 14, 2012, mass shooting that occurred at Sandy Hook Elementary in Newtown, Conn.

Valerie Block, senior marketing specialist for DuPont, agrees. “School districts across the country are concerned about safety after the Sandy Hook shootings, and as a result, there is more emphasis on security strategies to keep children safe in case of an attack,” she says. “Upgrading windows and doors with security glazing is being considered by a number of school districts, along with surveillance and alarm equipment, staff education and training, and emergency response procedures.”

Protective glazing in schools is also being driven by the need to protect against crime such as vandalism, says Michael Zizek of Vitrum. “With the higher media profile of vandalism, gang-related violence and rioting, we are seeing a significant shift towards security glazing. More and higher levels of security glazing are being specified by architects,” Zizek says.

Security glazing products allow architects to offer daylighting and views, while protecting occupants, and the glass industry offers a wide variety of solutions to designers facing a range of threat levels. See this issue's article, "How to Troubleshoot Common Coating and Ink Problems."

There are three main categories of security products: bullet resistant, forced entry and blast resistant. Security-rated glass products must undergo certification and testing from an outside test lab. The most widely recognized test standards are the Underwriters Laboratory, UL 752 Ballistic Standard, and National Institute of Justice, NIJ 018.01. The UL standard ranks products according to a UL-1 to UL-10 level (with UL-1 offering the lowest level of protection—a 9 millimeter firearm—and UL-10 the highest level, resisting a .50 caliber rifle).

According to Rick Snelling, vice president and general manager of Armortex, a supplier of security glazing products, bullet-resistant laminated glass offers UL Levels 1, 2 and 3. For even more protection, a laminated glass and polycarbonate unit can be supplied, meeting Levels 1 through 8. Snelling Snelling spoke in February at a security glazing seminar for architects, hosted by Bacon & Van Buskirk.

“Generally, if a school or private facility is seeking a greater degree of security beyond regular laminated glass, we’re recommending a UL-Level 3 series of B-R products,” Van Buskirk says. “Most architects and building owners seem to get the idea that resisting small arms is somewhat of a cost-effective product ‘threshold’. You could attempt to design for high-caliber rifles, bazookas and bombs, but at some point, cost becomes a factor.”

Fire-rated Glazing Trends

The trend toward security products has also made its way to the fire-rated market. “Due to heightened concerns regarding random acts of violence and terrorism, fire-rated security products that protect against forced-entry and ballistics are gaining interest,” says Jeff Griffiths, director of business development, Safti First. “Safti First now offers the first fire-resistive security glazing intended for detention and similar high-security applications,” he says. “We’ve added this product to our existing line of ballistic-rated, fire-resistive glass and framing systems.”

Fire-rated glass and framing suppliers continue to bring double-duty products to the market. From decorative to security to energy-efficient applications, companies are looking to fire-rated products that do more. In general, “we are seeing more performance products that give greater value and benefits to the user and designer,” says Ron Leiseca, eastern region sales manager, North America, Vetrotech Saint-Gobain.

On the energy efficiency front, fire-rated glass and framing manufacturers continue to promote the benefits of their products to bring daylight further into buildings, reducing electrical loads. “Fire-rated glazing is also being used to help fulfill daylighting goals in commercial and institutional buildings, where the need to retain visibility and access to daylight goes along with fire and life safety. Since line of sight may be drawn through interior glazing, building teams can now align expansive fire-rated glass in a range of interior and exterior settings to help draw light deep into a building’s core. This includes placing fire-rated glazing in line with non-fire-rated glazing and above open spaces in interiors,” says Jeff Razwick, president, Technical Glass Products.

The desire for daylighting means larger lites. “Manufacturers keep pushing the boundaries of what is possible to do with fire-rated systems, and the architects are following the lead. The larger glazing areas support the call for daylighting and improved aesthetics. So, there are more requests for entire glazed wall assemblies as opposed to smaller window openings,” says Peter Lindgren, president, Aluflam USA.

On the framing side, Lindgren says he is seeing a “dramatic increase” in specifications calling for fire-rated aluminum framing. “This is a result of increased market awareness of the various systems that are currently available,” he says.

Katy Devlin is editor for Glass Magazine. E-mail Katy at

  • Types of Security Glazing

    Bullet-resistant laminated glass

    Meets UL Levels 1, 2, 3

    Pros: scratch-resistant
    Cons: thick and heavy; greenish tint 


    Glass-clad polycarbonate

    (glass on the exterior and interior surface)

    Provides various protection levels, and is usable for applications such as detention glazing

    Pros: no tendency to warp; well suited for full-lite doors
    Cons: not UL 752 listed; scratch-resistant on one side only

    Laminated glass and polycarbonate

    (glass on the exterior surface, and polycarbonate on the interior surface)

    Meets UL Levels 1 through 8

    Pros: light and thin; UL Listed
    Cons: slightly more expensive

    Non-glass options


    (two plastic surfaces)

    Meets UL Levels 1, 2, 3

    Pros: lightest weight; clear
    Cons: most easily vandalized (shows wear and tear easily); expensive



    (often used in banks)

    Pros: Clearest of all the glazing types
    Cons: thick; will not protect above UL Level 3;
    susceptible to scratching (unless hard coated)

    Source: Based on a presentation from Rick Snelling, vice president and general manager, Armortex, delivered in February at a security glazing seminar for architects, hosted by Bacon & Van Buskirk.