A Better Backglazing Window System for Enhanced Office Security

Not every building that needs bullet-resistant windows can easily install them. For example, a building like the White House needs to protect occupants, but doesn't want to sacrifice the structure's historic character. Similarly, the upper-story offices of a government building might warrant the addition of bulletproof glazing that can stop a shot from a high-powered rifle. But just because they face a threat doesn't mean they have the budget (or clout) to easily absorb the cost of closing downtown streets and bringing in cranes to haul bullet-resistant windows into place.

In the realm of physical security, the answer is "backglazing." This refers to installing a layer of ballistic glass inside the existing window, creating a transparent backstop to catch bullets without disturbing the exterior of the building.

There are four primary reasons a facility turns to backglazing:

  1. Maintain the historical integrity of the exterior/facade
  2. Retain the architectural or aesthetic integrity of the building
  3. Increase security while leaving high-performance windows in place (i.e., keeping your self-tinting triple-pane insulated glass to meet LEED or occupant experience goals)
  4. Fully replacing windows would be prohibitively disruptive or expensive

Any backglazing project comes with the added benefit of increasing the physical security of your building without "tipping your hand" to outside attackers. But backglazing isn't a cure-all. While it solves many problems at once, it also creates its own complications.

Downsides of Backglazing

The primary downside of backglazing has always been that it complicates building maintenance.

If the backglazing isn't installed with an appropriate gap around the edge, there won't be proper airflow. This will lead to condensation forming between the exterior window and ballistic transparency. Depending on your building and weather conditions, this can get fairly extreme: foggy glass, frost on the windows, puddles on the window frame, and so on. But when the windows are installed with a proper edge gap, then the air flowing through will invariably carry dust with it, which will steadily accumulate between the window and ballistic glass.

The answer is to have backglazing that's robustly installed but can be easily removed by the building facility crew. But ballistic glazing is several times heavier than standard window glass. Usually, a bulletproof exterior window for an office weighs 100 to 200 pounds. A few storm-window clips aren't going to do it.

In the past, Total Security Solutions has addressed this by mounting their backglazing with a continuous gear hinge down one edge and a latching mechanism. But TSS CEO Jim Richard was never really satisfied with this.

"It's over-complicated," he explains. "That latch is one more thing to get snagged, bent, or jammed. Also, in my experience, when we make a window operable, we found that sometimes people decide to prop it open. What’s the point of that? Sure, now you've got a nice little ledge for your houseplant, but that houseplant isn't going to stop a bullet for you.”

But what bothered Jim most was that every other ballistically rated backglazing solution on the market was a one-off solution.

The TSS Removable Backglazing System

The TSS Removable Backglazing System is a standardized ballistic barrier retrofit system that works in any building. This system was entirely designed in-house and is manufactured in TSS's Michigan facility. It's been engineered by the same team responsible for TSS's True UL Framing system and Thermal Bullet Resistant frames—both industry firsts.


The system relies on a ballistically rated upper- and lower-carrier rail that secures the ballistic transparency in place, transferring its weight entirely to the building's structure. This makes it possible to use any ballistic glass, including LP1250 and glass-clad polycarbonate—extremely rugged, durable materials with high ballistic and forced-entry ratings. The framing system makes sure that every backglazing pane is installed with the appropriate gaps and airflow. The hook-and-channel system means that each pane can be lifted out (bearing in mind that ballistic glass is heavy—this may be a two-person job!) for regular cleaning.


"While you could go with any ballistic level, most tend to choose Level 3 or 4, given that these are exterior facing applications, where you might be concerned about a long-gun. Whenever appropriate, we like to steer building owners toward LP 1250 BR windows. This offers the best balance of cost, performance, and ease of maintenance in most applications.”

A Cost-Effective Bulletproof Glazing Solution for Any Building

Importantly, the TSS Backglazing System is an extremely cost-effective solution, both because it is standardized and because it is designed for easy installation (from the team who mastered the "overnight install" for bulletproof barriers). This savings is especially pronounced on upper story jobs, where replacing exterior windows with bullet-resistant glass might require riggers, cranes, street and office closures, special permits, and coordination with multiple city agencies and services. In such cases, choosing the TSS Removable Backglazing System can easily shave 25% of a project cost in ballistically securing upper-story windows. TSS also offers various options for hinged or fixed backglazing systems, depending on the project and desired aesthetics.

Blackgalzing-installation-interior"You go from closing down the street for a full business day to maybe moving a few desks before you leave for the night," Jim explains. "It would be hard to overstate what a difference it makes, now that we've standardized this. We’ve been offering various backglazing systems for a long time. Everyone has. There’s always been a need to increase security without changing the look and feel and facade of an existing building. But I've never been satisfied with these solutions. The industry was content to just cobble things together or give half a solution: it stops bullets, but looks clunky; it looks good, but it's hard to maintain; it looks great, but it costs a fortune. This is really a good solution: flexible, architectural, and really economical solution."

Have a ballistic project in mind? Backglazing might be the solution you're looking for. Contact a ballistic expert to learn more.

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