Technical information
Glass balustrades
A glass balustrade is a barrier that stops people falling from a stair, landing, mezzanine, balcony or terrace. The glass is either held in a frameless fixing (spigots or a base channel) so it stands on its own, or set between posts with a handrail. Every panel is toughened safety glass, and frameless panels are toughened laminated so the barrier stays in place if a pane breaks.
At a glance
- Glass
- Toughened 8, 10, 12 or 15 mm; toughened laminated 8.8, 10.8, 17.5 or 21.5 mm
- Toughening
- Toughened safety glass to BS EN 12150-1 on every piece.
- Edges
- Polished edges
- Holes and cut-outs
- Only where the fitting needs them, drilled from its template
- Sizes
- Each run drawn panel by panel; guarding at least 900 mm high inside and 1100 mm outside
- Priced
- By hand, from your design or drawings
Where it is used
- Staircases and landings
- Mezzanine and gallery edges
- Balconies and roof terraces
- Changes of level in gardens and around pools
- Shops, offices and public buildings
How it is priced
Draw your run in the balustrade designer to see every panel and fitting, or send us drawings. We check every balustrade and price it by hand, then send a written quotation with a drawing of each panel.
What we supply
Fixing systems in our balustrade designer
- Spigots (frameless)
- Glass held on stainless steel spigots fixed to the floor, with nothing between the panels. Glass: 12 mm toughened, 15 mm toughened, 17.5 mm toughened laminated, 21.5 mm toughened laminated.
- Base channel (frameless)
- Glass set into a continuous aluminium channel fixed to the floor or the side of the slab. Glass: 15 mm toughened, 17.5 mm toughened laminated, 21.5 mm toughened laminated.
- Posts and clamps
- Glass panels held by clamps between stainless steel posts. Glass: 8 mm toughened, 10 mm toughened, 8.8 mm toughened laminated, 10.8 mm toughened laminated.
Processing and the build-up
- Toughening
- Every panel is toughened to BS EN 12150-1 and carries its mark.
- Lamination
- Frameless panels with no handrail are two toughened panes bonded with an interlayer (BS EN ISO 12543 / BS EN 14449), so the barrier stays in place if one pane breaks (BS 6180).
- Holes
- Only where the fitting needs them, such as bolt-through spigots or standoffs, positioned from the fitting's drilling template. Holes follow the BS EN 12150-1 limits for toughened glass: at least as wide as the glass is thick, and clear of edges and corners by a multiple of the thickness. Our drawing checks every position before cutting.
- Made to measure
- Toughened glass cannot be cut, drilled, notched or edge-worked after it is toughened. Every size, hole and cut-out is fixed on the drawing before the glass is made.
- Heat soaking
- Heat soaking (BS EN 14179-1) lowers the small risk of a toughened pane breaking on its own from a nickel sulphide inclusion. Worth specifying overhead, above public areas or where a pane is hard to reach: tell us when your specification calls for it.
Regulations
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 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.
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.
Typical figures
| Use | Load at 1.1 m (BS 6180 / BS EN 1991-1-1) | System | Published glass build-up |
|---|---|---|---|
| Residential | 0.74 kN/m | Posts and handrail | 10 mm toughened |
| Residential | 0.74 kN/m | Frameless | 21.5 mm toughened laminated (10 + 1.5 + 10) |
| Public | 1.5 kN/m | Frameless | 25.5 mm toughened laminated (12 + 1.5 + 12) |
Typical only. The build-up for your barrier comes from the fixing system's tested data or the project engineer's calculation for the load, height and panel width. We print the confirmed build-up on the quotation drawing before anything is made.
Source: Balcony Systems, glass balustrade technical specification (read 28 October 2026).
Barrier loads and heights
| Where | Line load at the top | Infill (area) | Infill (point) | Minimum height |
|---|---|---|---|---|
| Domestic stairs, landings and floor edges | 0.36 kN/m | 0.5 kN/m² | 0.25 kN | 900 mm |
| Domestic balcony, Juliet balcony or roof edge | 0.74 kN/m | 1.0 kN/m² | 0.5 kN | 1100 mm |
| Flats, hotels and other residential | 0.74 kN/m | 1.0 kN/m² | 0.5 kN | 1100 mm |
| Offices and work areas | 0.74 kN/m | 1.0 kN/m² | 0.5 kN | 1100 mm |
| Stairs, landings and corridors in a public building | 0.74 kN/m | 1.0 kN/m² | 0.5 kN | 900 mm |
| Shops and retail areas | 1.5 kN/m | 1.5 kN/m² | 1.5 kN | 1100 mm |
| Restaurants, cafes and bars | 1.5 kN/m | 1.5 kN/m² | 1.5 kN | 1100 mm |
| Areas with fixed seating close to the barrier | 1.5 kN/m | 1.5 kN/m² | 1.5 kN | See Approved Document K |
| Assembly areas, shopping malls and crowds | 3.0 kN/m | 1.5 kN/m² | 1.5 kN | 1100 mm |
| Pedestrian areas in a car park | 1.5 kN/m | 1.5 kN/m² | 1.5 kN | 1100 mm |
Loads: BS EN 1991-1-1 UK National Annex, Table NA.8, as used by BS 6180. The line, area and point loads are separate cases, not added together. Heights: Approved Document K, Diagram 3.1. Check a barrier against these with our balustrade checker.
Installation
- The base, posts or spigots fix into a structure that can carry the barrier loads. Check the floor, slab edge or stringer before fixing; the fixings are part of the barrier's design.
- Glass never touches metal. It sits on the setting blocks and in the gaskets supplied with the fitting, tightened as its instructions say.
- Set the panels level and plumb, with the gaps between panels shown on our drawing.
- Fit the handrail or top rail where the design has one, before the area is used.
- Laminated glass edges are sealed with a neutral-cure silicone that is compatible with the interlayer. Acetic (vinegar-smelling) silicone and solvent sealants attack the interlayer and the edge clouds.
- Protect the glass and fittings during building work, and remove the protective film only when the work around them is finished.
Care and cleaning
- Clean with warm water and a little washing-up liquid or a household glass cleaner, using a soft cloth, a chamois or a squeegee, then dry with a lint-free cloth.
- Never use scouring pads, wire wool, razor blades, scrapers or powder cleaners: they scratch the surface for good.
- Rinse off cement, mortar, plaster and brick-cleaning acid straight away. Left to dry they etch the glass and the mark cannot be polished out.
- Look along the edges once in a while. A chip or a deep scratch on toughened glass weakens the pane: tell us and we advise whether it should be replaced.
- Wipe stainless steel fittings with fresh water and dry them. Near the sea or a pool, do it every few weeks to stop brown tea staining.
- Once a year, check that caps, gaskets and handrail joints are tight and that no panel has moved.
Questions
Do I need laminated glass?
Where the glass stands on its own with no handrail across the top and guards a drop of more than 600 mm, BS 6180 asks for toughened laminated glass that stays in place if a pane breaks. Our designer offers laminated glass for every frameless system for that reason.
How high must the balustrade be?
In a home: 900 mm on stairs, landings and internal floor edges, and 1100 mm on balconies, Juliet balconies and roof edges (Approved Document K, Diagram 3.1). Other buildings need 1100 mm except on flights of stairs.
Can you cut or drill the glass on site?
No. Toughened glass cannot be cut or drilled after toughening, so every size and hole is fixed on the drawing first.
Who designs the structure?
The fixings and the structure they fix into are designed for the barrier loads by the system's maker or the project engineer. We supply and fit the glass to the build-up confirmed for your barrier.
Standards that apply
| Standard | What it covers |
|---|---|
| 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 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 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 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 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. |
Documents
The specification sheet carries this page's content with today's catalogue figures, in three printable pages.