There are two typical methods of proper film installation. Wet glaze installation replaces the rubber gaskets in the window frame between the face of glass and the glazing stop with a silicone sealant that fills the gap between the frame and glass. This method allows some flexibility in installation across different frame types. A mechanical attachment system involves applying a metal plate or cable over the window film and screwing this secondary frame into the window frame and the wall. It is a particularly strong option as it anchors the security film to the building’s frame. However, attachment systems will not work with every type of framing system.
Security film adhesives are specifically designed to have the strength required to disburse the potentially intense energy of a blast or attack and transfer that load across the window opening. Swapping out this more expensive product for standard silicone caulking that may be more readily at hand on a jobsite will weaken the resulting system. Additionally, some contractors fail to use enough adhesive, neglecting to overlap both the film and frame. This is not the time to scrimp on materials, as this also negates the film’s protective abilities.
Think whole system
Fire-rated and security glazing units also require careful attention to the supplies used to install the product. For example, a fire-rated glass ceramic must be installed using fire-rated setting blocks and ceramic glazing tape or closed-cell polyvinyl chloride (PVC) tape (per their fire-rated listing). A bead of silicone sealant may be used for cosmetic purposes, but the foundation of the installation must be fire-rated.
However, glazing units face another potential installation risk: non-adherence to important code requirements. Sometimes, fire-rated glazing units are required to be installed as a rated assembly, meaning within an approved frame and wall opening. Other times, a fire-rated window will have different requirements than the surrounding wall. Understanding code requirements are critical to maximizing fire protection, investment, and resources.
Stoneman Douglas High School in Parkland, Fl., is a tragic example of the need to look at the protection provided by a full wall system. Police reports note the shooter in the 2018 attack had attempted to shoot through a third-floor window to target students leaving the school. However, that particular window had been strengthened with hurricane glazing in accordance with local codes, and withstood initial attacks. On the other hand, the 150 x 760-mm (6 x 30-in.) glass inset within the classroom doors was a standard, unreinforced product. While the shooter could not breach the door, he was able to fire through the glass to unlock doors and enter classrooms.
It is understandable clients working with tight budgets may only want to strengthen key areas of a project. While this is an effective first step, it depends upon critically thinking about how best to layer protection and from where a threat would approach. Installation is the final opportunity to consider the products going into a project and how they all work together to protect building occupants.
Handle with care
As fire-rated and other security glazing products become applicable for increasing numbers of applications, more contractors find themselves dealing with these heavy, and somewhat delicate, products. To ensure the project gets the level of protection specified, it is critical to follow the manufacturer’s installation instructions to the letter. No matter how many windows or glass systems a contract has installed, fire-rated and other security glazing should always be treated with care. A security glazing product is only as good as its installation and the surrounding system keeping it intact.
Stephanie Miller leads marketing and communications for Vetrotech Saint-Gobain in North America. Miller can be reached at firstname.lastname@example.org.