Double Glazing Glass options

Critical locations

Since 1992 there has been a requirement in the England & Wales Building Regulations for robust or protected glazing in certain critical locations. This means the glass must either break safely, resist impact or be protected from impact by permanent guarding. Where Doubled Glazed Units are provided both sheets of glass will need to conform if people are likely to come into contact with the glass from either side (e.g. patio doors). All tempered (i.e. toughened) or laminated glass must (with minor exceptions) be marked in accordance with BS6206.

CN Glass safety

CN Glass safety

Homeowners are becoming increasingly aware about safety in their homes and visible etched markings on all panes is the only evidence of complying with British Standards BS6206.The diagram below shows the dark shaded areas as those requiring safety glass.

Small panes of 6mm annealed glass are suitable in critical locations if the area of the single pane is no more than 0.5m2 and the width of each pane is no more than 250mm.

Choose the right glazing for your project

Ordinary glass

This is called Annealed or Float glass

Safety Glass

This can be either Toughened, Laminated, Safety Wired Glass or Annealed glass with safety film applied to it.
Safety glazing is mandatory for new installations within 800mm of the floor in windows and partitions, and within 1500mm of the floor in doors and side panels. Glazing is marked in the corner with BS6206.

Security Glass

This laminated glass or Annealed glass with film applied to it.
When security glass is installed you must ensure there is an emergency escape route in case of fire.

Low Emissivity glass or Low E glass

The glass must be used in a double glazed window so that the special reflective coating, which is always placed inside the cavity, is protected from any damage

Decorative glass

This can be Opaque, patterned, Stained, Sandblasted or Etched.

Low E Energy Saving Glass

Low-E Energy Saving Glass can only be used for glazing as part of a Double Glazed Unit.

Low E Energy Saving Glass is designed to help insulate your home by keeping as much heat inside as possible. The glass has a transparent metallic coating on one side that reflects heat back into the room rather than allowing it to escape through the window. It also allows optimum amounts of sunlight to pass through the window.

There are two choices of Low E Energy Saving Glass, these are called Hard Coat and Soft Coat.

They both perform the same job but the soft coat has better thermal insulation, therefore reducing heat loss even further. The inner surface of the glass stays warmer thereby reducing the likelihood of condensation. And there is less of a yellowish tint or dusty appearance to the glass.

Low energy saving glass

Low E energy saving glass

Click the logo below for more information on energy efficient window glass.


Self-Cleaning, low maintenance glass

A transparent metallic coating applied onto the outside surface of the glass harnesses the power of both the sun and rain to efficiently remove dirt and grime such as dried water marks, dust, resin and insect residues. It will always be easier to clean and it will stay cleaner for longer. It is an excellent choice for areas of glazing that are hard to reach like roof areas.

Solar Control Glass

Annealed, Toughened or Laminated glass can have a metallic coating applied to provide a high-performance Solar Control glass.

It has a slightly bluish tint that enhances visual comfort by filtering light and offers good solar control performance, therefore keeping rooms cool during sunny periods. Particularly useful on conservatory roofs, and large windows and doors.

Glass units can also have a combination of all three of these metallic coatings.

Double Glazed Units with Internal Blinds

Internal Blinds is a system of blinds, which are assembled and permanently sealed within the double-glazing cavity. Once sealed in this totally dust free environment, the blinds require no cleaning, always appear new and are protected from damage, unlike external blind systems. Benefits also include enhanced sun shading features and it also enhances the u-value of a sealed unit.

The main advantages offered by internal blinds

  • Clean for life
  • Protection against damage by encapsulation
  • Maintenance free
  • No UV degradation
  • Improved solar control
  • Improved u-valves
  • 12.5mm slat available in white, beige and silver as standard
CN Glass sliding doors

Folding sliding doors fitted with Internal Blinds

The blinds are available in a choice of colours and can be ordered in either a Venetian or a Pleated variety. The external controls will be white/clear and all the blinds will be fully colour co-ordinated within the cavity.

Folding sliding doors fitted with Internal Blinds

CN Glass manufacture and supply a wide range of internal blind options throughout the UK. Please give us a call to discuss your individual requirements: 01295 263364