When the Mesopotamians first invented glass around 4,000 years ago, little did they know that one day humans would have such an array of glass products available, each offering varying capabilities in strength, transparency, temperature control and more.
Today, we recognise that glass is an important building material used within domestic, commercial and industrial settings, and it can perform a wide range of functions. From patterned glass that lets in light but maintains privacy, to toughened glass and laminated glass options - for everything from balustrades to shower screens.
Glass can also play a critical role in maintaining the temperature of a building, have a major impact on the natural light levels inside the building, and be integral to a building’s security, longevity, structural integrity and value.
So let’s get back to basics on the types of glass on the market, the features and benefits of each, and their most common applications.
Annealed, plate or float glass
Annealed glass, also known as plate glass or float glass, is the most basic form of glass and is the starting point for other more advanced forms of glass.
It’s made by melting a mixture of silica sand, soda ash, and limestone, and then floating it on a bed of molten tin, hence the name ‘float glass’. This process creates a uniform thickness and a flat surface, and annealed glass can be easily cut and processed.
However it isn’t overly strong or safe, and when broken results in large dangerous shards. Its use as a finished product has diminished as safety standards have increased over time, and today is most commonly used in domestic windows.
Toughened glass, also known as tempered glass, is four to five times stronger than annealed glass, making it commonly used in frameless and semi frameless applications such as glass balustrades, shower screens and commercial shopfronts and doors. It’s made by heating a sheet of annealed glass to over 600°C, and then rapidly cooling the surface. The different cooling rates between the surface and the inside of the glass result in a much stronger glass product.
Toughened glass is more resistant to breakage than annealed glass, and when it does break it shatters into small regular-sized fragments, rather than large unwieldy shards.
Laminated glass is produced by using heat and pressure to sandwich a very thin layer of poly vinyl butyral (PVB) or another polymer between the glass layers, creating a durable, shatter-resistant glass that can absorb shock and reduce noise.
Safety and security are both great features of laminated glass - the polymer interlayer reduces the risk of shattered glass fragments, and can also make it harder to break through the glass. The polymer interlayer can be used to apply other benefits to the glass such as colouring, fire resistance, UV protection, sound reduction and even structural integrity.
Laminated glass is a popular material in construction, used for things such as building facades and large-scale windows. Most car windscreens are also made from laminated glass.
Coated glass refers to glass that has been treated with a thin layer of material, often a metal oxide, to enhance its performance properties.
The coating improves the glass's thermal insulation, energy efficiency, and transparency. For example, low-emissivity (low-e) coatings can reduce heat loss through windows, while anti-reflective coatings can reduce glare and increase light transmission.
Patterned glass is glass that has a design or texture imprinted onto its surface. The patterns can be achieved through a variety of techniques, such as rolling the glass through engraved rollers, acid etching, or sandblasting.
Patterned glass treatments can serve both functional and aesthetic purposes. For example, it can be used to obscure visibility while still allowing light to pass through, making it a popular choice for bathroom windows and shower enclosures. It can also be used for decorative purposes, such as in interior design accents or furniture.
Insulated Glass Units (IGU)
Double glazing through the use of Insulated Glass Units (IGUs) significantly improves the thermal performance of windows, keeping warmth in throughout winter and heat out during summer. Also known as DGUs (Double Glazed Units) IGUs are window units made of multiple glass panels, sealed with a spacer and gas between them.
This is just a snapshot of the most common glass types available, with new combinations and innovations in glass coming to market all the time. Want to find out more about the right kind of glass for your needs? Get in touch with the friendly team at Express Glass for a chat.
We sincerely thank our Silver Partners Express Glass for this editorial.