What is wire glass?

Wire glass is the glass that has a wire mesh or chicken wire embedded in it. Wire glass is made from annealed glass, it can’t be tempered. Wire glass is half as strong as annealed glass.

The advantage of wire glass is that it will hold the pieces of glass together pretty well when it's broken. That is why you might see it in your old high school gym. Slamming into annealed glass is very dangerous because it will break into large dangerous pieces capable of causing fatal injuries. Wire glass would have been used until the 60’s and 70’s when tempered glass became more widely available. It was formerly considered a safety glass, but does not meet current standards to qualify. There are better, safer options for use in areas that may harm people.

Wired glass is considered a fire-glass not only because it offers some fire-resistance, but also because it remains in place when broken to help mitigate air flow and the spread of fire and smoke. It is still commonly used on commercial doors in hallways or stairwells as a fire-safety measure. The wire mesh layer is superior to laminated glass interlayer in resisting heat. It is recommended for use in small openings, not subject to human impact.