Building Regulations

Let's make sure we get it right!

The 'Regs'

The building regulations state that areas known as 'critical locations' should be glazed in safety glass.

The image above shows the areas that should be safety glass in blue.

The general rule is that if it's in a door it should be safety glass.

Safety glass can be laminated or Toughened. Toughened being the cheaper and more popular of the two.

Laminated glass, however, must be used in public buildings. Toughened is not allowed.

For more details on the current building regulations please contact your local authority.
Building Regulations that apply to Glazing Work 2023

There are new regulations that apply to Window ventilation (See Government web site for more information: Click Here)

Document L:
Centre Pane U-Value Unit Make-Up
Replacement Windows & Doors 1.2 4-16-4 (24mm) Pilkington KS Argon Filled
Roof Lights 1.6 4-10-4 (18mm) Pilkington KS Argon Filled
New Build & Extensions Centre Pane U-Value Unit Make-Up
Windows & over 60% Glazed Doors 1.0 4-16-4 (24mm) Pilkington Optitherm S1 Plus, Argon Filled
30-60% Glazed Doors 0.8 4-16-4-16-4 (44mm) Pilkington KS Argon Filled
OR 4-16-4-16-4 (44mm) Pilkington Optitherm S1 Plus, Argon Filled

Bromyard Glass supplies 3 types of Sealed Units


  1. Non Low-E Units - For replacement units only (Not replacement Windows)
  2. Standard Low-E Units - Pilkington KS, Argon Filled. For replacement Windows. (These may or may not come up to Regulations for New Build & Extensions. We advise customers to confirm with their Building Control)
  3. Optitherm Low-E Units - Pilkington Optitherm S1 Plus, Argon Filled. For New Build & Extensions.

Document Q:


Applies to:


  • New Residential Build and Extensions to existing properties
  • Windows and Doors that have accessible area with 2 metres.


For example: Ground Floor/Flat Roof/Sloping roof all must have 6.8mm Laminated at least in one pane of unit.


Windows/Door that do not comply with above that have no locking handles or locking faculties must also have 6.8mm Laminated in one pane of the unit.



Document O:


Applies to:


  • Residential Buildings (Houses and Flats)
  • Homes and Schools where people can sleep on the premises
  • Student Accommodation
  • Living accommodation for Children aged over 5
  • Shared communal rooms.
  • Work places that have living accommodation


Glass should have minimum G Value of 0.4 and light transmittance of 0.7



Conservatories:


Do not need to comply with Document L if all of the below apply:


  • Less than 30sq Metres Floor Area
  • On Ground Floor Level
  • Not connected to property heating
  • Has portable Heating only
  • Wall/Door/Window connected to property does comply



Document N:


Glazed areas that have a danger that they can be walked into must have visual markings for people to see.



Replacement Glass:


Any replacement glass must be of equivalent U-Value or better.


For example: If you are replacing a 4/16/4 Low E Double Glazed Unit, you would not be permitted to replace it with just Clear glass. You would have to replace it with the same or improve it’s U-Value by using Warm Edge Spacer Bars and Gas filling the unit.

The above information is given in good faith and for guidance only. All data is based upon average values. The purchaser shall be responsible for determining the suitability of this product for their purposes.