Heat Treated vs Fully Tempered

There are two distinct categories of heat-treated glass products, heat-strengthened and fully tempered, differentiated by the degree of residual compression and/or the edge compression that exists in the material after heat treatment. We are happy to help you determine which option is the most appropriate for your project.

In addition to the improved solar performance, insulating glass offers a greater availability of coatings. Low-E coatings which cannot be exposed, and therefore cannot be used with monolithic glass, can be used inside the insulating unit where they are protected by the hermetically sealed space.


Fully Tempered Glass

Fully tempered glass is glass that has been heat-treated to have a minimum surface compression of 10,000 psi (69MPa), making it approximately four times stronger than annealed glass of the same thickness and configuration. Tempered glass is considered a safety glazing material because it dices, or crumbles, when broken, leaving no large shards and reducing the risk of serious injury. These characteristics make fully tempered glass ideal for applications where strength is paramount or in cases where a human might reasonably impact glass.


Heat-Strengthened Glass

Heat-strengthened glass is glass that has been heat-treated to have a surface compression between 3,500 and 7,500 psi (24 to 52 MPa), making it approximately twice as strong as annealed glass of the same thickness and configuration. Unlike fully tempered glass, heat-strengthened glass is not considered a safety glazing material. Accordingly, heat-strengthened glass is the preferred product for projects that do not require safety glass but are likely to be met with thermal or mechanical loads.

Safety Certified

Press Glass, Inc. Safety Glazing Products are permanently marked with a logo that contains information regarding test standards, classification, thickness and location of manufacture. This logo also represents our commitment to excellence and is your assurance of quality and compliance with both ANSI Z97.1-2009 and 16 CPSC 1201 standards.