08/25/2026
🔥 Glass Class: What Makes Glass Fire-Rated?
Not all glass can stand between you and a fire. Here is what separates the ones that can.
Fire-rated glass is engineered to maintain its integrity for a specific duration during a fire, typically rated at 20, 45, 60, or 90 minutes. But what actually makes it different from standard glazing?
There are two main categories. Ceramic fire-rated glass uses a crystalline structure that withstands thermal shock, meaning it will not shatter when exposed to extreme and sudden heat changes. Tempered fire-rated glass is heat-strengthened beyond standard tempering levels and often combined with intumescent interlayers that expand when heated, creating an insulating barrier.
Where does fire-rated glass show up? Stairwell enclosures, corridor partitions, lobby separations, and exit pathway sidelites in commercial buildings. Building codes across Ontario mandate specific fire ratings based on occupancy type and proximity to exits.
Choosing the wrong rating or installing non-rated glass in a fire-rated assembly is not just a code violation. It is a life safety issue.
Need fire-rated glazing assessed or installed in your building? Our team knows the codes and the products inside out.
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