Glass Toughening

Toughened glass is a form of safety glass (also called tempered glass) that has been heated to a very high temperature (typically over 600°C) and then rapidly cooled with jets of air in a controlled process. This heat treatment changes the internal structure of the glass, making it significantly stronger than standard float glass.

As a result, toughened glass is typically around five times stronger than standard glass of the same thickness. Toughened glass is typically required where safety, and safety standards, require additional safety. Examples of applications include glass stables, shower screen glass, frameless glass doors and some forms of balustrade glass.

Tempered glass is another term for toughened glass – they are the same thing. Read our in-depth guide to toughened and tempered glass.

The process of producing toughening glass involves several stages:

1. Cutting and shaping the glass first – All cutting, drilling, polishing, and shaping must be completed before the glass is toughened, because toughened glass cannot be cut after it has been heat treated.
2. Heating the glass in a furnace – The glass is heated in our Gaston toughening plant evenly to over 600°C.
3. Rapid cooling (quenching) – High-pressure air is blown onto the glass surface to cool it quickly. This heating and rapid cooling hardens the surface and creates tension inside the glass, which gives toughened glass its strength.

Toughened glass is typically 5 times stronger than glass that has not been toughened. However, one of the key benefits of toughened glass is how it breaks.

When standard glass shatters, it breaks into large sharp shards which can cause serious injury. When toughened glass breaks, it shatters into small fragments, significantly reducing the risk of serious injury. Because of this, toughened glass is classed as safety glass and is stipulated by building regulations for many applications.

No. Glass cannot be cut, drilled or shaped once it has been through the glass toughening process. All processing must be completed before the glass is toughened. This includes:

• Cutting to size
• Drilling of holes
• Shaping by routing or waterjet
• Edge polishing and beveling

If toughened glass is cut or drilled after toughening, it will shatter.

Toughened safety glass is recommended or required when glass is:

• In doors or low-level glazing
• Used in bathrooms or wet areas
• Used in furniture or shelving
• Used in public or commercial buildings
• Used where impact risk is high
• Where stipulated by building regulations

Our toughened glass complies with the British and European standard BS EN 121 50. For more information about this safety standard, read our in-depth article

Toughened glass is commonly used in areas where strength and safety are important considerations or where stipulated by building regulations. Examples of common applications include:

• Shower screens and shower doors
• Glass doors and partitions
• Glass balustrades and balconies
• Tabletops and shelving
• Shop and office interiors

In many of these applications, building regulations require safety glass such as toughened, laminated or toughened and laminated glass.

If you require glass toughening, we have the capacity and expertise to supply toughened and tempered safety glass in bulk or single sheet quantities and we are trusted suppliers to many UK bathroom, kitchen, and furniture manufacturers.

To order toughened glass we require either measurements, for simple square and rectangular glass sheets, or a hard template or digital DFX files. We can scan hard templates to produce the DFX cutting files we require. If you are a manufacturer, we can hold glass sizes on file for production and delivery to meet your production schedules. If you have questions about ordering toughened glass, please do contact us.

We operate a fleet of delivery vehicles staffed by our own drivers, ensuring the highest standards of customer and product care. Our delivery service is free, with weekly delivery routes operated throughout the south of England. Regular delivery areas are shown on the map below. We can deliver glass to areas outside of our usual delivery area for large projects. Our free delivery service accommodates both single sheets of glass and bulk orders.