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Safety Glass: Is Laminated Glass or Toughened Glass the Best Option?

Safety glass is required for use in ‘critical locations’ in domestic buildings to protect people from accidental injury. Both laminated glass and toughened glass are used as safety glass in different situations.

Safety glass can be laminated or toughened glass

Glass is a superior material, but windows, doors and large expanses of glazing can be lethal to a person if they break upon impact from accidental collision. For this reason, to protect people there are strict regulations for the use of safety glass.


What is safety glass?

Safety glass is different to standard annealed float glass by the way it has been treated and how it breaks on impact. Annealed glass will break into large jagged shards that can pierce or cause deep life-threatening cuts to a person or animal.


To be called safety glass, the glass must pass testing to measure the impact it can withstand before it breaks and how it breaks.


There are three types of safety glass:

  • Laminated glass
  • Toughened (or tempered) glass
  • Wire mesh glass

In this guide, we are going to focus on the two most common domestic types of safety glass: laminated and toughened glass.



What is safety glass used for?

Safety glass is used in any area deemed a ‘critical location’ where there is a risk that if the glass could break it would cause serious harm and injury.


The main applications of safety glass are:
  • Low-level windows
  • Glazing in doors
  • Balustrades
  • Glass stairs
  • Glass floors
  • Furniture such as shower screens, tables and worktops

We outline below what is a ‘critical location’ and when safety glass is required.

Do you want safety glass in your doors or windows?

All Everest doors and windows are available with a choice of different glass, including safety toughened or laminated.

What is the difference between toughened and laminated glass?

Toughened glass and laminated glass are often confused with each other, although they are different products manufactured in a different way. Each has its own benefits and applications.


Laminated GlassToughened Glass
European Standard Number: BS EN 14449European Standard Number: BS EN 12150
Can be 'broken' and crackedIs four times stronger than ordinary glass
Is held together by the PVB layer, which is difficult to pierceShatters into small granular pieces with dulled edges for safety
Required in car windscreensRequired in windows up to 800mm from ground level and 1,500mm for doors with glazing
Enhanced noise reductionNo noise reduction
Enhanced UV resistanceNo UV resistance
Chosen for security or safetyChosen for safety
Usually has a B/2 class ratingUsually has the highest safety rating A/1
More expensive but offers more protectionMore economical and used more often as safety glass

Laminated glass

Laminated glass is made by sandwiching a polyvinyl butyral (PVB) layer of thin plastic between two panes of annealed glass and fusing them together. The PVB thin layer is a minimum of 0.38 mm thick and can be used in multiples to create more resistance (for example, bulletproof glass) – 0.76mm is usually the maximum thickness for domestic glass.


The unique quality of laminated glass is that if it breaks, the glass is fused to the PVB layer and stays in place. For this reason, it’s used in skylights or glass ceilings to avoid glass shattering and falling from above.


Laminated glass is also used for car windshields and the cockpits of airplanes to avoid glass being sprayed into the face and eyes if the windscreen should shatter at speed.



The benefits of laminated glass

Security

Laminated glass is useful for additional security on secluded doors and windows to the rear of a property. If the glass is broken by an intruder, it’s difficult to pierce and gain entry because of the PVB layer.


UV resistance

The PVB layer will reduce the transference of UV and solar gain which makes it a useful application for south-facing windows to protect furniture.


Noise reduction

Laminated glass can help with noise reduction because the PVB layer disrupts sound waves as they pass through the glass. Sound can be reduced by up to 40dB which has the effect of seeming to move the sound further away.


Safety

In domestic properties, laminated glass will protect adults, children and pets from damage if a glazed door should break from impact.



How to tell if glass is laminated

As the laminate layer is so thin, unless you have a trained expert eye, it’s difficult to detect any perceptible difference in the glass. The only way to see the PVB layer is at the edge of the glass, but that would usually be hidden in a glazed unit.


Safety glass should be marked by a kitemark and the Standard for laminated glass is: BS EN 14449.

Do you want safety glass for your doors or windows?

All Everest windows and doors are available with a choice of different glass, including safety toughened or laminated.

Toughened glass

Toughened glass is sometimes known as tempered glass or safety glass. The glass is four times as strong as standard annealed glass and if broken, shatters into small granular pieces that don’t have sharp or jagged edges.


Toughened glass is made when annealed float glass that has been cut and finished to size is heated to 620˚C. The point just before the glass softens.


The glass is then rapidly cooled with cold blown air.


This process causes the outer surfaces of the glass to harden before the centre of the glass and this creates a compressive stress. The interior of the glass is held under tensile stress by the compressive stress of the outer layers.


The stress and tension is what creates the enhanced strength of the glass. It also makes the glass break in an explosive manner which produces the small cube-like fragments of shattered glass.


The benefits of toughened glass


Safety

Toughened glass shatters into small cube-like pieces without sharp or jagged edges. These granular pieces are less likely to cause harm and have a reduced risk of piercing or deep cuts.


Strength

Four times stronger than standard annealed glass and stronger than laminated glass. Toughened glass is more difficult to break.


Economical

Toughened glass is not as expensive as laminated glass, so is often used as safety glass unless laminated is specifically required.


Heat resistant

Toughened glass also has more resistance to heat and temperature variations. For this reason, it’s used for worktops and cooking splashbacks.


What is laminated glass used for, what is toughened glass used for?

Laminated GlassToughened Glass
Glass stairs/balustradesLow-level windows
Glass floorsShower screens
Shop frontsSplashbacks/shelves
Aquariums/animal enclosuresWorktops
Jewellery display casesTabletops
Windscreens
UV resistance/solar control
Glazed entrance doors

Which is stronger laminated or toughened glass?

Toughened glass is physically stronger than laminated glass and harder to break.


However, laminated glass is designed to not shatter or splinter when broken and that avoids injury by holding the glass on the PVB layer.


Toughened glass is designed to shatter into granular pieces that don’t have jagged or sharp edges.


Safety glass Standards & Regulations in domestic buildings

All domestic glass installed in what is deemed a ‘critical location’ is required to meet British Standards and Building Regulations.


Critical locations

Critical locations in domestic buildings are usually areas that could cause serious injury or pierce upon impact, such as doors, door side panels, low-level glazing in walls or partitions.



Critical locationAreaStandard Rating (minimum)
Glazing in doorsWithin 1500mm from floor levelBS 6206 C
BS EN 12600 3B3
If smallest dimension is more than 900mmBS 6206 B
BS EN 12600 2B2
Glazing adjacent to doorsWithin 300mm of the edge of a door and within 1500mm from floor levelBS 6206 C
BS EN 12600 3B3
If smallest dimension is more than 900mmBS 6206 B
BS EN 12600 2B2
Low-level glazingWithin 800mm of the floor levelBS 6206 C
BS EN 12600 3B3
ExemptionsIf smallest dimension is less than 250mm and area less than 0.5m2, glass is 6mm thick
Glass protected by a suitable barrier

Safety glass classification and marking

For Building Regulations, safety glass used in critical locations must be visibly marked to show compliance. The mark must contain the following:

  • The manufacturer’s name or trademark of manufacturer
  • European Standard number e.g EN 14449
  • Classification from the EN 12600 (or 6206) impact test: 2B2


European Standard Number

  • Laminated glass BS EN 14449: Glass in Building – Laminated and laminated safety glass – product standard
  • Toughened glass BS EN 12150: Glass in Building – Thermally toughened soda lime silicate safety glass

Impact test classification

The British (& European) classification for the impact test:

  • BS 6206:1981 Specification for Impact Performance Requirements for Flat Safety Glass and Safety Plastics for use in Buildings (Partially superseded but remains current and is cited in Building Regulations)
  • Superseded by BS EN 12600:2002 Glass in building - Pendulum test - Impact test method and classification for flat glass

The impact test

Impact is measured using a pendulum test. A 45kg leather bag filled with lead shot is dropped from varying heights to simulate impact at different levels of force. The higher the force resistance, the higher the Safety Standard rating.



BS EN 12600BS 6206Drop heighttest simulationSafety glass
1B1A1200mmAdult running into glassToughened glass
2B2B450mmAdult walking into glass, but not runningLaminated glass
3B3C190mmChild running into glass, adult pushing against glassWired glass

References from:

Everest offers laminated glass or toughened glass as an option in all windows, doors and conservatories. We also follow all Building Regulations to ensure that the correct safety glass is installed where required.


Talk to us about safety glass for your windows or doors.

FAQs

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    Is safety glass the same as toughened glass?

    Safety glass is often thought to be toughened glass or tempered glass.


    Safety glass is defined by meeting various Building Regulations and British Standards by testing.


    Both laminated glass and toughened glass can be used as safety glass if they meet requirements.

  • +
    Is safety glass a legal requirement?

    In areas deemed ‘critical locations’ safety glass is a requirement of Building Regulations.


    Critical locations in domestic buildings are usually areas that could cause serious injury or pierce upon impact, such as doors, door side panels, low-level glazing in walls or partitions.


    The areas considered ‘critical locations’ include from floor level to 1500mm for glazed doors, from floor level to 800mm for low-level windows and 300mm wide from the side of a door in glazing adjacent to a door.

  • +
    Is toughened glass breakable?

    Yes. Toughened glass is four times stronger than standard annealed glass but it can still be broken by force.


    When toughened glass breaks, it shatters into small granular cube-like pieces that don’t have sharp or jagged edges to avoid piercing and injury.

  • +
    Can you break laminated glass?

    Laminated glass is made from two panes of glass fused together with an internal layer of PVB.


    Laminated glass can be broken, but the pieces of glass will hold together on the PVB layer to avoid injury. The laminate layer is difficult to pierce and offers more security from intruders.


    Standard laminated glass can eventually be pierced, but it does take considerable effort. Different weights of PVB layering offer more resistance to piercing.

When safety is paramount in your home

Everest offers laminated glass or toughened glass as an option in all windows, doors and conservatories.

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