Glass as a building material has been known to us since ancient times. The main disadvantage of the material was its brittleness, which limited its usage. However, with the development of manufacturing technologies and testing methods, today we can work with the two types of safety glass – laminated and toughened glass. These are resistant to mechanical stress and, therefore, superior to standard annealed glass.
Many customers are wondering what kind of glass would be a better choice: toughened or laminated glass? While it is impossible to answer this question unequivocally because one or the other type will be ideal for specific conditions and purposes of use, learning more about the key differences will help you make an informed decision.
Join us as we go through the technology of manufacturing both laminated glass and toughened glass, their advantages and drawbacks, as well as features and areas of application.
What Is Laminated Glass?
Laminated glass is a type of safety glass that consists of two or more layers of glass (usually, annealed float glass) and one or more layers of plastic interlayer that is usually made from EVA (ethylene-vinyl acetate) or PVB (polyvinyl butyral). The layers are glued together using special pressure and heat to keep the glass firmly bonded to a thin film after breaking.
When broken up, the plastic sheet in the laminated glass holds the whole structure together, meaning that it’s not going to break into tiny pieces. Laminated safety glass is designed to stay intact when shattered, leaving no dangerous shards scattering in the surrounding area and removing any danger from broken glass.
- Impact-resistance and non-shattering design. In case of impact, laminated glass does not break into sharp pieces but instead cracks. The plastic interlayer acts as a barrier that prevents flying glass shards. Thus, laminated glass is ideal for areas with high traffic or vulnerable groups of people, such as schools and hospitals.
- UV resistance. Laminated glass has a UV filter that protects against harmful sun rays, making it ideal for both homes and offices.
- Resilient against high temperatures. In case of fire, the plastic interlayer is not degraded. Therefore, laminated glass provides much better protection against fire than standard glass.
- Sound reduction properties. The middle layer of laminated glass also acts as a sound barrier, providing better acoustic insulation.
- Higher cost. Laminated glass is more expensive than standard glass, as the production process requires additional materials and time.
- Weight. Laminated glass is also heavier than regular glass and therefore more difficult to handle.
Laminated safety glass is often used in the construction of large buildings and glazing, such as shop windows, balustrades, and canopies. It is also used in automotive applications (such as car windscreens) and aircraft windows.
Laminated glass is considered to be a safer and more durable alternative to standard glass, making it perfect for places where enhancing security is a top priority – such as domestic and residential buildings, ground floor glass, as well as external and internal doors.
What Is Toughened Glass?
Toughened glass, also known as tempered glass, is a type of safety glass that is made by subjecting annealed glass to intense heating to its softening point and then being very rapidly cooled.
The tempering process makes the glass stronger, more durable, and heat-resistant. As a result, the glass becomes harder to break and more resistant to impact, as well as has much greater load and breakage resistance than standard glazing.
Thanks to its incredibly durable outer layer, tempered glass is up to five times stronger than regular or laminated glass of the same size and thickness.
However, when toughened glass breaks, it splits into several hundred small blunter pieces of glass (as opposed to large jagged shards), in contrast to laminated glass that remains solid when damaged.
- Safety and durability. Toughened glass is much stronger than standard glass and therefore more resistant to impact and mechanical stress. In case of breakage, the glass shatters into small pieces with blunt edges, reducing the risk of injury, usually associated with falling glass.
- Incredible heat resistance. Tempered glass can withstand temperatures up to approximately 250°C (470°F) without breaking.
- Thermal shock resistance. Toughened glass is able to withstand sudden changes in temperature, making it ideal for areas with extreme weather conditions.
- Better breakage resistance. Due to its increased strength, tempered glass needs to be hit a lot harder than other types of safety glass to break.
- Easy access for the intruders. In areas prone to vandalism and break-ins, toughened glass won’t be the best solution for increasing safety. Even though it is stronger than regular glass, when tempered glass does break, it will shatter completely, leaving the entrance entirely exposed. As a result, burglars can gain entry into your property relatively easier than in the case of laminated glass.
- Costly replacement. Since a small injury can cause the entire tempered glass window to break apart entirely, the replacement costs will be higher, as you’ll have to replace the whole window.
Toughened glass is used extensively in areas where regular glazing would not be strong enough to withstand mechanical stress, heat, or cold. This type of safety and heat resistance glass is often used in the construction of large buildings, such as high-rise office blocks, glazing, shop windows, balustrades, canopies, and so on.
Some other uses include skylights, shower screens, and household appliances, such as oven doors.
Toughened glass is also used in a wide range of automotive applications. Tempered safety glass is used in car windscreens, side and rear windows, sunroofs, as well as in the manufacturing of glass doors and partitions.
Laminated Glass vs. Toughened Glass: Which Is Better?
So, what type of glass should you choose for your specific project – laminated or toughened glass? There is no single answer to this question. The ideal type of safety glass to choose depends on a variety of factors, including the specific purpose of using the glass, the environment in which it will be used, and your budget.
For example, if you’re looking for a type of glass that will provide better security for your home or office, then laminated safety glass is a much better option than toughened glass. Laminated safety glass will stay intact when shattered and won’t allow burglars to easily gain entry into your property.
On the other hand, if you’re looking for a type of glass that can withstand extreme temperatures and won’t break easily, then toughened glass would be a better choice. Tempered glass is much stronger than regular glass and can withstand high temperatures and sudden changes in temperature without breaking.
Below, you’ll find answers to a few hottest questions regarding choosing between toughened and laminated glass.
How can you tell the difference between the toughened and laminated glass?
There are a couple of simple ways to check if you have laminated or toughened glass without trying it break it. For instance, you can tell if you have laminated glass by checking if there’s a visible interlayer on its edge.
Other than that, you can look for a printed kitemark code in the corners of the glass to check the type of safety glass:
- BS EN 14449 – laminated glass,
- BS EN 12150 – toughened glass.
Can you walk on toughened glass?
Toughened glass is very strong and can withstand a lot of stress. Its layers bonded together to form a safe and strong surface, suitable to walk upon.
For instance, there are walk-on flat glass rooflights – a popular option for those who want to let in more light inside without sacrificing an inch of terrace space available on the roof.
Can burglars break laminated glass?
Laminated glass is more difficult to break than ordinary glass, but it’s not unbreakable. However, when laminated glass does break, it doesn’t shatter into tiny pieces but instead cracks. The plastic sheet holds the glass together, making it much more difficult for burglars to gain entry into your property.
Which glass is safe for a house?
If you’re looking for a type of glass that will provide better security for your home, then the laminated glass is a much better option than toughened glass, as it reduces the possibility of a serious injury should the glass break.
Can tempered glass break on its own?
Impurities in tempered glass can cause it to spontaneously explode, creating dangerous openings and raining glass on anyone around.
For this reason, it’s imperative to order toughened glass products only from reputable manufacturers that are open about the materials they use as well as their manufacturing process in general.
Can you get toughened laminated glass?
Yes, there is such an option. Toughened laminated glass will be a combination of laminated glass and toughened glass.
This means that you get two panes of toughened glass held together by an extremely tough PVB plastic interlayer, resulting in an extremely durable and heat-resistant glass, capable to withstand extreme pressures and less prone to breakage.