Donovan Mirror and Glass

Serving Southeastern Wisconsin

Heat-resistant Glass

Our ordinary plate glass is a soda-lime glass. Whether it is annealed or tempered is just a matter of how quickly it was cooled from a high temperature state. When referring to heat-resistant glass people are usually speaking about borosilicates and glass-ceramics. We have included ordinary tempered glass here as well since it is commonly used for some high-temperature applications.

Tempered Glass

Service temperature 400° F to 450° F

Extreme temperature 500° F

High co-efficient of thermal expansion - less resistant to thermal shock

Common uses: kitchen hot plates, fireplace screens (usually not door glass)

Pyrex™ - a borosilicate

Service temperature 450° F

Extreme temperature 900° F

Low co-efficient of thermal expansion - less resistant to thermal shock

Common uses: Fireplace doors, halogen light covers, wood stoves, and more.

Robax™ - a glass-ceramic

Operational temperature range -400° F to 1400° F

Extreme temperature 1400° F

Very low co-efficient of thermal expansion - very resistant to thermal shock

Common uses: Fireplace doors, halogen light covers, wood stoves, and more.