Maximum Sizes for Toughened and Laminated Glass

22.02.2021

Glass types

  1. Annealed
  2. Toughened
  3. Laminated

 

Toughened Glass

Toughened glass is four to five times stronger than normal glass of equivalent thickness. It is mainly used for safety & strength. Toughened glass is difficult to break and when on breakage it will break into small, relatively harmless fragments. This substantially reduces the likelihood of injury to people, as there are no jagged edges or sharp corners like normal glass. 

As the thickness of toughened glass increases, its resistance to impact and pressure increases and it is less likely to bow or warp under stress. 

The size of the toughened glass sheet required will also affect the necessary thickness: the bigger the area, the thicker the glass must be.

As you would expect, the thicker a pane of toughened glass is, the stronger it is. So which thickness do you need to specify when designing your architectural glass feature.

Determination of safe thickness of glass

Once the type of glass to be used is selected, section deals with the determination of appropriate thickness of glass. The thickness of the glass to be used in window panels is governed by the following factors: 

  • Area to be covered by the window panel,
  • Support conditions on sides (framed, partly framed, unframed)
  • Aspect ratio of glass panel,
  • Effective wind pressure at the window height,
  • Strength/load bearing capacity of glass to be used

4mm thoughned glass

  • 4mm annealed glass should not exceed 1300mm square, 
  • Maximum area for 4mm thoughened glass: 2.2m2
  • Maximum sizes: 2500mm x 1500mm
  • Maximum aspect ratio: 8:1

Limits for 5mm toughened glass:

  • Maximum area: 3m2
  • Maximum sizes: 3100mm x 1900mm
  • Maximum aspect ratio: 8:1

Limits for 6mm toughened glass:

  • Maximum area: 4m2
  • Maximum sizes: 2500mm x 1500mm
  • Maximum aspect ratio: 12:1

Limits for 8mm toughened glass:

  • Maximum area: 6m2
  • Maximum sizes: 2500mm x 1500mm
  • Maximum aspect ratio: 12:1

Limits for 10mm toughened glass:

  • Maximum area: 8m2
  • Maximum sizes: 2500mm x 1500mm
  • Maximum aspect ratio: 20:1

Limits for 12mm toughened glass:

  • Maximum area: 4m2
  • Maximum sizes: 2500mm x 1500mm
  • Maximum aspect ratio: 12:1