What tempered glass means
Tempered glass is heat treated to be much stronger than regular glass and to break into small, blunt pieces instead of sharp shards.
Also called safety glass.
Where it matters on a glass job
It cannot be cut after tempering, so measure exactly before ordering. Each tempered pane carries a permanent mark, which is what an inspector looks for in hazardous locations.
What the model code says
- Each pane of glazing in hazardous locations carries a visible manufacturer's designation naming the type of glass and the safety glazing standard it meets. (IRC 2021, Chapter 3)
Check which code edition your building department enforces for tempered glass before you quote.
What it costs
The window glass replacement cost guide has the typical job at $380 and the usual range at $180 to $880. The guide shows its sources and what moves the price. The window glass replacement cost calculator prices a job line by line.
Work it out
- Free calculator: Window glass replacement cost calculator
- Cost guide: Window glass replacement cost
- Tools, templates and guides: Free glass resources
Sources: 2021 International Residential Code, Chapter 3, Building Planning (ICC). Checked October 9, 2026.