FAQs on Toughened glass

Exterior toughened glass wall inside a modern building

Throughout both residential and commercial properties, toughened glass is utilised for a number of reasons. But, primarily, it is because of the difference in strength between it and regular glass panes. 

What is Toughened Glass?

Toughened glass, also known as “tempered” or “safety glass,” is simply a stronger version of the standard glass used in the majority of the windows in a home. It is used in places where more strength or safety is required, such as doors, windows that are close to doors, or windows that are at low levels.


The resultant glass can endure compression of at least 10,000 pounds per square inch and is up to 6 times stronger than standard glass. Additionally, compared to conventional other glass products, it is up to 500% more heat- and shock-resistant.


When tempered glass breaks, tiny, dull pebbles rather than razor-sharp shards result. As a result, toughened glass is much safer and it utilised in both residential and commercial properties. 

How Toughened Glass is Made

During the manufacturing process, glass panels are strengthened so that once they are installed, they are heat-resistant and will not shatter on heavy impacts. Typically, toughened glass can be made in two ways.

Hot and Cold

The majority of toughened glass is created using a process called tempering. This involves glass products heated to a temperature of about 620°C before being abruptly cooled with cold air jets. 


As a result of this procedure, the glass’s exterior gets compressed while the interior is left to float for a while (creating tension on the inside). The number of residual stresses will be larger and the final glass will be stronger the higher the glass’s thermal expansion and the lower its thermal conductivity.

Chemical Reactions

On the other hand, glass can be strengthened through a chemical reaction. This process involves immersing the glass in a 300°C potassium salt bath. The separation of the salt into ions is evident when it dissolves. The sodium ions in the glass surface can now be replaced with potassium ions. Since potassium ions are 30% bigger than sodium ions, the outer surface is compressed while the inner surface is left unchanged. 


As a result of the internal tension created, the glass is strengthened and will withstand large impacts.

Different Types of Toughened Glass Products

Toughened glass also is versatile when it comes to style. At Prentice, we stock a variety of safety glass products, including toughened glass, heat-strengthened glass and toughened laminated.


It can also be cut into any shape or size to meet the customer’s specific requirements. The annealed glass will first be cut into the preferred shape and then tempered afterwards. Ready for installation by a reputable glass London company.   

The Benefits of Toughened Glass 

For both residential and commercial properties, there are several benefits of toughened glass. As the name suggests, this type of glass product is around 6 times as strong as regular glass. In homes, owners do not have to worry about losing any natural light as a result of the strengthening, as toughened glass has the exact same light transmission as single-paned. For a business, this is also ideal as it will stop any would be thieves or severe weather conditions from damaging anything inside. Toughened glass is also extremely heat-resistant, meaning it can withstand temperature fluctuations up to 250°C.


Tempered glass is extremely difficult to break. However, in the rare cases that it happens, it will do so into very small, blunt cube-shaped fragments that do not result in serious injuries. Perfect for homes with small children or pets. In addition, due to its high durability, frequent replacement is unnecessary. As a result, toughened glass can be used for a very long time.

Our London and Surrey Glass Company  

Here at Prentice Glass, we have over 70 years of experience in the glazing industry and are one of the oldest glass London companies still operating today. Our team of specialists cater to your individual needs on any project, ensuring that your requirements are met with double-glazed and toughened glass installation. 


For more information, or to receive a quote, fill in our form here. Or, follow us on Facebook and stay up to date with the latest news and our biggest projects to date. 

– Get In Touch –

Contact Us