Glass Glossary

Float Glass


Last Updated: November 23, 2023

Float glass is a type of flat, transparent glass manufactured using the “float process,” where molten glass is floated on a bed of molten metal, usually tin. The result is a smooth, uniform, and distortion-free sheet of glass. The float process was invented in the 1950s by Sir Alastair Pilkington.

There are multiple types of float glass, distinguished by their composition and properties:

Regular Float Glass: Also known as clear float glass, it is made from sand, soda ash, limestone, and other raw materials. Due to the presence of iron oxides in the materials, it has a natural greenish tint. It’s commonly used in windows, doors, and other architectural applications and can be further processed into laminated, tempered, or insulating glass.

Low Iron Float Glass: This type of glass is similar to regular float glass, but with reduced iron content, resulting in higher light transmittance and less color distortion. It’s ideal for applications requiring high visibility and clarity, such as display cases, aquariums, and architectural facades. An example of low iron glass is Cardinal’s Purevision™, which offers superior clarity and brightness compared to regular float glass.