The Art of Glass - Types of Glass

Glass is produced and fabricated for various applications of use. To help you understand the differences in glass, we have outlined the 4 major glass types below and what applications they are most used in.

FLOAT Glass:
Float glass is composed of silica sand, limestone, dolomite and soda ash among other materials and is heated to 2900°F. Next, the molten liquid is poured into a tin bed that floats the liquid down a line and forms the liquid to glass at the dimensions specified. Float glass provides a controlled thickness and goes through controlled cooling processes that create Annealed Glass.

Low Iron Glass:
Low iron glass
is composed of silica and other materials and throughout the manufacturing process at least 90% of the iron is removed to ensure the clearest glass is produced. High iron glass where the iron is not removed, appears to have a green tint.



Annealed Glass:
Annealed glass is cooled very slowly throughout the float glass manufacturing process. Most glass arrives as standard float glass which allows additional fabrication techniques to take place. Annealed glass has many benefits like its resistance to impact or thermal stress and breaks into large, irregular shards.

Heat Strengthened Glass:
Heat strengthened glass heats to 1200°F. and is then force cooled slowly. Heat strengthened glass is made by compressing the surface and edges of the glass, hardening the outer 20% of the glass. Heat strengthed glass is roughly twice as strong as annealed glass that is manufactured at the same dimensions.

Heat strengthened glass retains the normal properties of annealed glass but does not meet ANSI Safety Glazing Requirements.

Tempered Glass:
Tempered glass heats to 1200°F and is force cooled quickly to enable tempering to occur. Tempered glass creates a higher surface and edge compression than heat strengthened glass where the outer surface is twice as hard as the inner material. Tempered glass is 4 to 5 times stronger than standard annealed glass and meets ASTM Code C1048 standards.

The beauty of tempered glass, is that when broke, it shatters into tiny fragments with rounded edges to ensure injury is at a minimum, while also meeting glazing requirements and safety concerns. Applications of tempered glass range from doors, windows, and glass markerboards.

Laminated Glass:
Laminated glass is exactly what the name perceived, two layers of glass laminated to an interlayer. The interlayer is usually comprised of EVA or PVB materials depending on applications of use and is placed between two layers of annealed or heat strengthened glass.

Laminated glass allows a decorative film, coating or opaque color or fabric textile to be positioned between the glass for aesthetics. Laminated glass is most commonly used as hurricane impact glass.

All Ghent glassboards are manufactured using tempered safety glass following manufacturing and fabrication industry standards as well as BIFMA glass standards ensuring your Ghent glassboard will never bow, strain, or fall from the wall.