Safety glazing is glass that either breaks safely, resists impact or is protected by a screen, and building regulations require it where people are likely to walk or fall into glass. These critical locations mainly cover glazed doors, panels beside doors and low-level panes. The rules apply across the UK, but each nation has its own regulations and guidance documents.
What is a critical location for glazing?
A critical location is a part of a wall, door or partition where accidental impact with glass is most likely, so the glass there must be safe if someone falls against it. In practice the guidance in every UK nation focuses on three zones: glazing in doors, glazing in panels close to doors, and glazing near floor level in windows, walls and partitions.
The heights used in England, Wales and Scotland are similar. Their guidance describes glass within 800mm of floor level, glass in a door up to 1500mm above floor level, and glass within 300mm of the edge of a door up to 1500mm. The exact wording, diagrams and referenced standards differ, so the nation-by-nation sections below set out which document applies where.
- Glass in a door, up to 1500mm above floor level
- Glass in a panel within 300mm of a door edge, up to 1500mm
- Glass in a window, wall or partition within 800mm of floor level
What are the safety glazing rules in England?
In England, requirement K4 of the Building Regulations 2010 says glazing that people are likely to contact while moving in or about a building must break in a way unlikely to cause injury, resist impact without breaking, or be shielded or protected from impact. The guidance is Section 5 of Approved Document K, 2013 edition, and Diagram 5.1 shows the critical locations using reference heights of 300mm, 800mm and 1500mm.
In a critical location, Approved Document K offers three approaches. Glass can meet the safe breakage test, which means Class 3 of BS EN 12600 or Class C of BS 6206, rising to Class 2 or Class B for doors and door side panels with a pane wider than 900mm. Alternatively, the glazing can be robust or in small panes, or it can sit behind a permanent protective screen.
Approved Document K also deals separately with manifestation, meaning markings, logos or patterns that make large areas of clear glass visible so people do not walk into them. That guidance is aimed at shops, offices and other non-domestic buildings and does not apply to dwellings, although the impact safety rules for critical locations do.
What are the safety glazing rules in Wales?
In Wales, glazing safety guidance is in Approved Document N, Glazing: safety in relation to impact, opening and cleaning, published by the Welsh Government for use in Wales as the 1998 edition incorporating 2000 and 2010 amendments. Requirement N1 covers protection against impact. The other Part N requirements, on manifestation, safe opening and closing of windows and access for cleaning, do not apply to dwellings.
Approved Document N describes critical locations as glazing in walls and partitions between floor level and 800mm, and glazing in doors and door side panels between floor level and 1500mm. The Welsh Government's guidance on replacing doors and windows sets out the same zones, including glass within 300mm of a door up to 1500mm. Safe breakage is defined by reference to BS 6206, with Class C as the standard and Class B for door and side panels wider than 900mm.
| Nation | Legal requirement | Guidance document | Standards referred to |
|---|---|---|---|
| England | Building Regulations 2010, Schedule 1, requirement K4 | Approved Document K (2013 edition), Section 5 | BS EN 12600, BS 6206 |
| Wales | Building Regulations 2010, Schedule 1, requirement N1 | Approved Document N (1998 edition incorporating 2000 and 2010 amendments) | BS 6206 |
| Scotland | Building (Scotland) Regulations 2004, standard 4.8 | Technical handbooks, domestic and non-domestic | BS 6262-4 |
| Northern Ireland | Building Regulations (Northern Ireland) 2012, regulation 96 | Technical Booklet V, Glazing (October 2012) | As set out in Technical Booklet V |
What are the safety glazing rules in Scotland?
In Scotland, the Building (Scotland) Regulations 2004 set functional standards and the Scottish Government's technical handbooks explain how to meet them. Collision with glazing is dealt with under standard 4.8, danger from accidents. Separate domestic and non-domestic handbooks are published and updated periodically, so check the edition that applies to your project.
The 2022 domestic handbook says glazing should be designed to resist human impact as set out in BS 6262-4 where all or part of a pane is within 800mm of floor level, part of a door leaf, or within 300mm of a door leaf and within 1.5m of floor level. The glass should either not break or break safely, or vulnerable glazing should be guarded. It also covers manifestation, which within dwellings is generally needed only where glazing installations are unusual.
What are the safety glazing rules in Northern Ireland?
In Northern Ireland, glazing is covered by Part V of the Building Regulations (Northern Ireland) 2012, regulations 95 to 99. Regulation 96, impact with glazing, requires reasonable provision to limit the risk of people sustaining cutting and piercing injuries from accidental impact with glazing. The other regulations in Part V deal with transparent glazing, safe opening of windows and safe access for cleaning.
Guidance on meeting these regulations is in Technical Booklet V, Glazing, published by the Department of Finance in October 2012. It gives the guidance on ways of meeting regulation 96 and the other glazing regulations, including the types of glass or protection that are acceptable. Check the booklet, or ask the council's building control team, for the detail that applies to a particular door, screen or window.
What do BS EN 12600, BS EN 12150 and BS EN 14449 mean?
BS EN 12600 is the pendulum impact test for flat glass. It classifies glass into classes 1, 2 and 3 using drop heights of 1200mm, 450mm and 190mm, and records how it breaks: Type A for annealed-style breakage, Type B where the pieces stay held together, as with laminated glass, and Type C for the small fragments typical of toughened glass. A result is written as a code such as 1(C)1 or 2(B)2.
BS EN 12150-1 is the product standard for thermally toughened safety glass, covering fragmentation, tolerances and edgework. BS EN 14449 is the product standard for laminated glass and laminated safety glass, covering conformity and factory production control. A pane can carry its product standard and its BS EN 12600 class together.
BS 6206 is the older British impact standard that Approved Document K and Approved Document N still refer to, and BS 6262-4 is the British code of practice on glazing safety related to human impact, currently published as BS 6262-4:2018.
Do safety glazing rules apply to replacement windows and doors?
Yes. When a complete window or door is replaced, the new glazing should meet current safety glazing guidance even if the glass it replaces did not. The Planning Portal's guidance for England and the Welsh Government's guidance both say safety glazing should be provided to any glass in a critical area when windows and doors are replaced. A replacement window or door is also checked against other building regulation requirements.
In England, the Planning Portal says building regulations will not normally apply where work amounts to no more than replacing broken glass. Even so, if a broken or misted unit sits in a door, a side panel or a low-level pane, fitting toughened or laminated safety glass is the sensible choice. Our glaziers note the safety glass needed for each pane at survey and list it on the written quote.
How is safety glass marked?
Safety glass is normally given a permanent mark in one corner that should remain visible once it is fitted. The mark usually identifies the manufacturer or processor, the product standard it was made to, such as BS EN 12150 or BS EN 14449, and often its BS EN 12600 classification. Older safety glass may show BS 6206 instead.
The mark is the simplest way for a householder, landlord or building control officer to confirm that the right glass has been fitted in a critical location. If glass in a door or low-level panel is unmarked and its type cannot be confirmed, treat it as ordinary glass. Replacing it with marked safety glass removes the doubt.
Frequently asked questions
Does glass in a door always have to be safety glass?
In practice, yes. The guidance in England, Wales and Scotland treats glass in a door as being in a critical location, up to 1500mm above floor level, and Northern Ireland's regulations require protection against cutting injuries from impact with glazing. Door glass should be toughened or laminated safety glass, or otherwise meet the guidance. Side panels next to doors are treated the same way.
Do the rules require me to upgrade existing glass?
Building regulations apply when building work is carried out, so they do not generally require existing glass to be upgraded. Unmarked glass in a door or low-level panel may still be ordinary annealed glass, which breaks into sharp pieces. Replacing it with marked safety glass is a sensible precaution, especially in homes with children or in rented property.
Does secondary glazing need to be safety glass?
The guidance is about where glass is, not what kind of window it is in. Secondary glazing inside a low-level window, or close to a door, sits in the same zone people can fall against, so it should be safety glass in those positions. Laminated or toughened glass is commonly used in secondary glazing for that reason.
What does a code like 1(C)1 or 2(B)2 on glass mean?
It is the BS EN 12600 impact classification. The first number is the class, where 1 is the highest and is tested from a 1200mm drop. The letter shows how it breaks: B for laminated glass that holds together and C for toughened glass that breaks into small pieces. The last number is a further class result from the same test.
Are the safety glazing rules the same across the UK?
The principles are the same, but the documents are not. England uses Approved Document K, Wales uses Approved Document N, Scotland uses its technical handbooks under the Building (Scotland) Regulations 2004, and Northern Ireland uses Technical Booklet V under its 2012 regulations. The critical heights in England, Wales and Scotland are similar, but the referenced standards and wording differ.
Sources
- Approved Document K: Protection from falling, collision and impact – GOV.UK
- Doors and windows: building regulations – Planning Portal
- Approved Document N: glazing (safety in relation to impact, opening and cleaning) – GOV.WALES
- Building regulations: doors and windows – GOV.WALES
- Building standards technical handbook 2022: domestic – 4.8 Danger from accidents – gov.scot
- The Building Regulations (Northern Ireland) 2012, regulation 96 – legislation.gov.uk
- Building regulations technical booklets – Department of Finance NI
- BS EN 12600:2002 Pendulum test: impact test method and classification for flat glass – BSI
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