TL;DR
Tempered glass is glass heat-treated in a furnace and rapidly quenched so its surfaces hold compression, making it roughly four times stronger than annealed glass and causing it to crumble into blunt pebbles instead of shards when it breaks. Building codes mandate it as safety glazing in hazardous locations: in and beside doors, near tubs and showers, and in large panes close to the floor, per IRC R308.
What it means
Tempered glass is glass heat-treated in a furnace and rapidly quenched so its surfaces hold compression, making it roughly four times stronger than annealed glass and causing it to crumble into blunt pebbles instead of shards when it breaks. Building codes mandate it as safety glazing in hazardous locations: in and beside doors, near tubs and showers, and in large panes close to the floor, per IRC R308. Each lite carries a permanent etched bug in a corner certifying compliance, and it cannot be cut after tempering.
Where it sits in the glossary
Tempered glass is part of the Trade jargon group inside the ProFix Directory glossary. Browse every term in this category from the glossary index.
Why Ohio homeowners should know it
This is a term Ohio homeowners encounter when reading contractor quotes, hiring paperwork, or inspection reports. Understanding it well enough to ask one good follow-up question is usually all the protection a homeowner needs.
ProFix Directory keeps definitions short on the index page and saves the longer context — Ohio-specific rules, where the term comes from, and which ProFix tools touch it — for these per-term pages so the term is easy to cite and easy to share.
ProFix tools that touch this term
See also
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