Types of Glazing

You may think that glass is glass but the truth is that no one type of glazing is suitable for every application.  This is why there are so many different types of glazing available.  Read on to learn more.

Toughened Glass

Toughened glass is stronger and has higher compressive stress than annealed glass of the same thickness.  This means that it is more resistant to impact breakage, it is able to withstand uniform loads better, and decreases the risk of thermal stress breakage.  If it is broken, it shatters into small fragments, thus preventing major injuries.  Toughened glass may be heat treated, or chemically strengthened.  Toughened glass is necessary in areas that have a high risk of human impact such as glazed doors, bathrooms, and windows over 1.5m tall.

Laminated Glass

Like the glass in windshields, laminated glass may crack on impact, but the fragments tend to adhere to the protective layer rather than fall and potentially cause injury.  Laminated glass gives better protection to people and property than other glass products.  The standard two-ply construction of laminated glass provides resistance to penetration when subjected to attempted forced entry.  Laminated glass is effective for sound control.  It also blocks 99 percent of UV rays from entering your home.

Tinted Glass

Tinted glass reduces heat gain and glare in the home.  Spectrally selective glazings absorb and reflect the infrared portion of sunlight while still transmitting visible daylight, meaning that your view is unaffected.  The main uses for tinted glass is to reduce the glare from outside, reduce UV fading to furnishings, and decrease the amount of solar heat gain through windows.  The most common colours are green, grey, and bronze.  The colour density in tinted glass will increase as the glass thickness does.

Patterned Glass

Patterned glass is made by squeezing semi-molten glass between two rollers, one of which has a surface pattern, and creates a continuous, permanent impression onto the soft glass ribbon.  The pattern is imprinted onto just one surface, while the other side remains relatively smooth.  The glass is then cooled before being cut to size.  Patterned glass usually only transmits slightly less light than clear glass.

Reflective Glass

Reflective glass has either a vacuum-deposited thin-film metal coating or a pyrolytic coating.  The vacuum-deposited coatings are soft, and for protection and longevity, they must be deployed inside an insulating glass cavity.  Pyrolytic coatings are baked onto the surface while the glass is still hot.  They are hard and durable and are normally glazed with the reflective surface to the exterior.

High Transmission Low Emissivity (low-e) Glass

Low-e glass has a coating that allows daylight from the sun to pass into the house but reduces the amount of the long-wavelength infrared heat that can escape through the window.  Low-e glass has a coating that reduces the amount of solar heat gain while still maintaining good levels of visible light transmission.

Insulating Glazing Units

Insulating glazing units or IGUs are commonly referred to as double or triple glazing.  The performance of IGUs depends on the properties of each layer of glass and the thickness, sealing, and content of the cavities between the glass layers.  The cavities must be sealed to prevent convective heat transfer.  The cavities may also be filled with an inert, low-conductivity gas such as argon.  The cavity between the panes of glass ranges from 6mm to 18mm.  The wider the cavity, the better the U-value.