Blog 6. Part 2

When security is a priority, is laminated Glass the best to use?

Laminated glass is two or more sheets of glass bonded together with a plastic inter layer, this inter layer holds the glass together and will be retained in the frame in the instance that either or both of the glass sheets should break. It is therefore a safety glass and can be used in Residential & Commercial Skylights, Glass Bridges, or Flooring.

Annealed glass is not as strong as toughened glass and is susceptible to thermal fracture. This is caused when there is a significant temperature difference within the same piece of glass and is likely to occur where adjacent structures or trees, for instance, could cast a shadow across the glass with part of it in the sunshine and part in shade. It can also be caused by other finishes being located close to the underside of the glass where heat coming in through the glass is reflected back to the outside. This can be caused by wide upstands or the fitting of blinds in close proximity.

Heat-strengthened laminated glass is considered the most suitable option for most general use glass Retractable Roof Systems. It is similar to annealed laminated glass, except the glass sheets that are laminated together have been heated strengthened. This glass is twice the strength of annealed glass and is resistant to thermal heat stress cracking and does not suffer from the small risk of Nickel Sulphide inclusions that may affect some toughened glass.

Heat-strengthened laminated glass is a more expensive option, but it offers one of the broadest specifications for Overhead Glazing, as it is considered a Safety Glass which will be retained in the frame if broken and is not susceptible to thermal heat stress cracking. A Walkable Skylights & Glass Roofs with a heat strengthened laminated inner pane would be classified as non-fragile.

Toughened laminated glass is similar to annealed laminated glass except for the sheets of glass that are laminated together have been toughened and heat soak tested.

This glass has all the benefits of toughened glass but without the risk of glass pieces falling from the Glass Facade if one or both glass sheets in the laminate should break.