Glass is a common material that is widely used in buildings by architects and designers. The use of glass in the building allows the light to come in and create a feeling of space, to fulfill the idea and concept of a modern and stylish building design. The glass actually can be made in many different ways and for various applications. It can be engineered into special properties in terms of its optical level, chemical, thermal, and other mechanical properties. We will briefly introduce the most common types of glass for commercial applications.
Annealed Glass / Float Glass
Annealed glass is also known as standard or float glass. It is the basic flat glass that hasn’t undergone any tempered or heat-strengthened process that makes it easier to break into jagged shards. The term of annealed is referring to the cooling process of the glass where the things are melted at 2700 degrees Fahrenheit and floated on a pool of molten tin. The molten glass is slowly cool in a controlled way to room temperature. This process helps to release its internal stress that may cause breakage if the glass is not annealed properly. Annealed Float glass is a quality glass that has excellent optical clarity. It is suitable for use as double glazing windows or large window panes due to its stylish and modern look. It can also be used as a base product for more advanced glass types that require further processing.
The glass will usually be heat-treated for achieving a higher level of safety and durability before using as building materials or other commercial applications. There are two types of heat-treated glasses, one is heat-strengthened glass and another is tempered glass. The production process of these two types of glass is quite similar, both involve the use of the same processing equipment, with the same procedure which is heating the glass to nearly 1200 degrees Fahrenheit and then undergoing the force-cooling process to crease surface compression.
Heat-Strengthened Glass
Heat-strengthened glass is also known as semi tempered, semi toughened glass, or partially toughened glass. The heat strengthening process and the cooling process have induced compression stress on the glass surface while the center stays in tension. This process has increased its thermal strength and mechanical strength which made it twice as strong as the untreated glass or annealed glass. However, the cooling process of heat-strengthened glass is slower than then tempered glass, which results in a lower compression strength than tempered glass. To classify as heat-strengthened glass, it is required to have a surface compression ranging from 3500 psi to 7500 psi without the requirement for edge compression. When the heat-strengthened glass is broken, it will be broken into fragments that are similar to the annealed glass, but more likely to break into larger pieces from edge to edge. Heat-strengthened glass is not a safety glass and is unable to use for human impact applications.
Tempered Glass
Tempered glass is also known as toughened glass. In order to create a stronger and safer glass, the cooling is accelerated by a uniform blast of air on both surfaces which makes a higher surface and edge compression to the glass, the air-quench temperature and other variables create a surface compression of at least 10,000 psi. The process has made the tempered glass four to five times strong than the untreated glass or annealed glass. In this case, the tempered glass is less likely to encounter a thermal break. It is most commonly to be used in applications where higher safety characteristics are required or where requires significant strength to withstand wind press or thermal stress. Some common applications are balustrades, glass doors, tabletops, showcase enclosures, or other building structural applications. To classify as tempered glass, it is required to have a surface compression of at least 10,000 psi or an edge compression of not below 9700 psi. When the tempered broken, it fractures into small and regular pieces which are typically in square fragments that are less likely to lead to injuries.
Laminated Glass
Any one of the glasses we mentioned above can be undergone the lamination process. Laminated glass is made of two or more layer of glass that has one or more inter-layers of polymeric materials that are bonded between the glasses. It can provide extra safety and security since it uses multiple layers to support the structure and if there is any broken or cracked, the shatters will be kept in place, adhering to the plastic vinyl interlayer until it is replaced or secured. This has greatly reduced the hazed from the shattered glass fragments. The most popular finished product is two sheets of tempered glass, laminated together with a Poly Vinyl Butyral (PVB) interlayer. Another common interlayer is the SentryGuard Plus (SGP) which has a higher post breakage strength and ability to withstand severe weather conditions with its excellent performance properties. It can offer 5 times tear strength and 100 times the rigidity of the conventional PVB interlayer. Other common polymers such as Ethyl Vinyl Acetate (EVA) is also often to be used with other materials to get desired decorative or color effects. The interlayer offers extra benefits as well such as fire resistance, sound dampening, or other features that can be embedded in the interlayer.
Due to its high safety properties, laminated glass is commonly used where there is a high possibility of human impact or the glass could fall to cause injury if shattered. It is used extensively in the building products, transport, and automotive industries such as glass floors, overhead glazing, bulletproof glass, balustrades, etc.
Insulated Glass Units
Insulated Glass Units (IGUs) is also known as double glazing or double pane glass window. They consist of two or more glass panes separated by a spacer which is filled by gas or air and then sealed completely to prevent the entering of air from outside. IGUs are used to prevent heat loss through our doors or windows. The gas used between the glass panes is usually argon, krypton, or a mixture of both to form the insulating barrier. The layer of gas diffuses the heat transfer to provide more energy efficiency and cost reduction on heating and cooling. When compared to single glazing, IGUs reduce conductive heat loss or gain by more than 50%. The performance of the IGUs is greatly depending on the thickness of the glass and the space between the glass panes. The wider the spacer, the more efficient and expensive the window. An additional coating of Low-E can provide thermal insulation at the same time allow the light to come in the house to be more energy-efficient.
Insulated glass units are used in residential and commercial buildings. The common applications are vertical glazing, overhead glazing, skylights, sloped glazing, etc.
MecHero Malaysia supplies quality glass for a wide range of products and construction applications. You can always contact us at +6011-7000 7687 or email us at my.mechero@gmail.com for an inquiry about the glass suppliers in Malaysia. As a steel and online hardware store in Malaysia, we also supply a wide range of steel materials, general hardware, or mechanical components. Tell us your requirements now and we can advise you accordingly.
Photo credit: Media from Wix, glazcon, vitroglazings, glazcon