Standards and regulations

The standards our glass is made to, and what the Building Regulations ask of glass in England. Wales, Scotland and Northern Ireland publish their own guidance, which is close but not identical. A building control body or the project engineer has the final word on any building.

Building Regulations, explained

Approved Document K, section 5 (requirement K4)
Glazing in a critical location must break safely (BS EN 12600 class 3 or better), be robust, be in small panes, or be protected. Critical locations: any glass in a door or within 300 mm of a door edge up to 1500 mm above the floor, and any glass in a wall up to 800 mm above the floor. A pane wider than 900 mm in a door or door side panel needs class 2.
England. This section took over the former Approved Document N.
Approved Document K, section 3 (requirement K2), Diagram 3.1
Guarding is needed where people could fall: in a home where the drop is more than 600 mm, and in other buildings where it is more than 380 mm. Minimum heights: 900 mm on stairs, landings and the edges of internal floors in a home; 1100 mm on external balconies, Juliet balconies and roof edges; in other buildings 1100 mm, except 900 mm on flights of stairs and 800 mm in front of fixed seating.
England. The guarding must also resist the loads of BS EN 1991-1-1 and its UK National Annex.
Approved Document K, section 3
Where children may be present, guarding should not be easy to climb and a 100 mm sphere should not pass through any opening in it.
Homes, and buildings likely to be used by children.
Approved Document O (overheating), with Approved Document K section 3
Approved Document K asks for guarding 800 mm high at opening windows. Where an upper-floor window in a home is opened to stop overheating, Approved Document O asks for guarding at least 1100 mm high.
New homes in England (Approved Document O, 2021).
Approved Document K, section 7 (requirement K5.2)
Large areas of glass that people could walk into, such as glass doors and screens, carry marking at two levels: 850 to 1000 mm and 1400 to 1600 mm above the floor.
Buildings other than homes, and glazed doors and screens where they could be mistaken for an opening.
Approved Document A (structure)
A floor, roof or canopy, and the glass in it, must carry the loads of its use safely. The project engineer sets the load class from BS EN 1991-1-1 and confirms the glass and its supports.
England. Walk-on glass, roof lights and canopies.
Approved Document L (conservation of fuel and power)
A new or replacement roof light or window must meet the limiting U-value set in Approved Document L. The U-value comes from the whole unit's make-up and frame, not from the glass alone.
England. Roof lights, windows and doors in heated buildings.
Approved Document M (access to and use of buildings)
Doors in buildings other than homes need a minimum clear opening width, an opening force a wheelchair user can manage, and glass that is easy to see. The door is drawn to these on the quotation drawing.
Entrance doors and doors in partitions in buildings other than homes.
Part K under review
The Building Safety Regulator opened a call for evidence on Part K in October 2026. The current Approved Document K applies until a new edition is published.
England.

Check where safety glass is needed with our glass safety checker, and a barrier's load and height with the balustrade checker.

Standards register

Standard	What it covers
BS EN 572Glass in building. Basic soda lime silicate glass products	Float glass (part 2) and patterned glass (part 5): the base glass every other product starts from, its dimensions and quality.
BS EN 12150-1Glass in building. Thermally toughened soda lime silicate safety glass. Definition and description	What toughened safety glass is, its fragmentation test, flatness and edge work, and the limits for holes and notches. Every toughened pane carries a mark naming the standard.
BS EN 14179-1Glass in building. Heat soaked thermally toughened soda lime silicate safety glass. Definition and description	Heat soaking: toughened glass held at about 290 °C so that panes with a nickel sulphide inclusion break in the oven rather than in the building. It lowers the risk of spontaneous breakage; it does not remove it.
BS EN 1863-1Glass in building. Heat strengthened soda lime silicate glass. Definition and description	Heat-strengthened glass: about twice the strength of annealed glass, breaking into larger pieces that tend to stay in the frame. Not a safety glass on its own; used laminated.
BS EN ISO 12543Glass in building. Laminated glass and laminated safety glass	Laminated glass: two or more panes bonded with an interlayer that holds the pieces together if the glass breaks. Part 2 covers laminated safety glass.
BS EN 14449Glass in building. Laminated glass and laminated safety glass. Evaluation of conformity / Product standard	The product standard under which laminated glass is declared and marked.
BS EN 12600Glass in building. Pendulum test. Impact test method and classification for flat glass	The impact test that classes safety glass. The class is written X(Y)Z: X and Z run from 3 (lowest drop height) to 1 (highest); Y is how it breaks: A like ordinary glass, B holding together like laminated glass, C in small pieces like toughened glass.
BS EN 356Glass in building. Security glazing. Testing and classification of resistance against manual attack	Security classes for laminated glass, from P1A (dropped-ball tests) to P8B (axe tests).
BS EN 1279Glass in building. Insulating glass units	Sealed double and triple glazed units: their durability, gas retention and marking.
BS EN 1096Glass in building. Coated glass	Glass with a surface coating: low-emissivity, solar control and self-cleaning coatings.
BS EN 1036-1Glass in building. Mirrors from silver-coated float glass for internal use	Silvered mirror glass: the silver and protective backing layers, quality and the edge corrosion test.
BS EN 16477-1Glass in building. Painted glass for internal use. Requirements	Glass painted on one face for interior use, such as splashbacks and wall cladding.
BS EN 14428Shower enclosures. Functional requirements and test methods	What a shower enclosure must do, including its stability, its resistance to impact and the safety glass it is made with.
BS EN 14072Glass in furniture. Test methods	Impact test methods for glass in furniture, such as table tops and cabinet doors. Shelves and glass supported over its whole area are outside it.
BS 6180Barriers in and about buildings. Code of practice	How barriers, including glass balustrades, are designed: loads, heights, and when the glass must stay in place after it breaks.
BS 6262-4Glazing for buildings. Code of practice for safety related to human impact	Where safety glass is needed in buildings and how to select it.
BS 5516-2Patent glazing and sloping glazing for buildings. Code of practice for sloping glazing	Glazing laid at a slope or overhead, such as roof lights and canopies: why the lower pane should hold together if it breaks.
BS EN 1991-1-1 and UK National AnnexEurocode 1. Actions on structures. Densities, self-weight, imposed loads for buildings	The loads a floor or barrier must carry, by type of use. Table NA.8 of the UK National Annex gives the horizontal loads on barriers.
BS 6206WithdrawnImpact performance requirements for flat safety glass and safety plastics for use in buildings	Withdrawn and replaced by BS EN 12600. Older drawings and documents still quote its classes A, B and C.

Standards are published by BSI. We summarise what each covers; the standard itself governs.