Heat Strengthened and
Fully Tempered Glass
What is the difference between heat-strengthened (HS) and fully tempered (FT) glass? How do I determine which is needed for my project?
Heat-strengthened (HS) glass has been subjected to a specifically controlled heating and cooling cycle and is generally twice as strong as annealed glass of the same thickness and configuration. Contrary to tempered glass, heat-strengthened glass is not a safety glass product as defined by Russian building codes. It is intended for general glazing and is usually the choice for commercial applications where additional strength is desired to withstand wind load and thermal stress, but the strength of tempered glass is not necessary or required by building safety codes. HS glass or tempered glass can’t be cut or drilled after heat-strengthening and any alterations, such as edge grinding, sand blasting or acid etching, can cause premature failure. Tempered glass is several times stronger than regular annealed glass of the same thickness and configuration. When broken, it usually breaks into many relatively small fragments. This type of glass is usually intended for sliding doors, storm doors, building entrances, bath and shower enclosures, interior partitions and other uses requiring superior strength and safety properties.