Guidance for structural glass and balustrade design
Glass balustrades are a popular design feature for the home and for commercial properties. When specifying the use of glass balustrades in any project, there are a number of considerations that should be included in your design to ensure safety and best use of glazing type and fixings.
The Building Regulations and supporting Approved Documents, identify the relevant building standards and minimum requirements that should be applied to the use and design of structural glass and balustrades as well as any building control checks. Please note, additional standards apply regarding the reaction to fire classification of laminated glass used in external balconies in residential buildings (and other 'relevant' buildings) that exceed 18m in height – see Building Regulation 7 and Approved Document B, requirement B4.
Particular areas you should address include:
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The specification of glazing used in balustrades: is the specified glazing type fit for purpose and sufficiently strong, particularly when used in public spaces?
Consider:
- Which type of glass is more appropriate to use (for example: monolithic toughened glass or laminated glass) when protecting people from falling and/or from being hit by falling glass?
- Risk of breakage due to nickel sulphide inclusions or impact from sharp objects. Falling glass due to a failure in the fixings, which is usually caused by unsuitable fixings being specified or fixings being substituted or incorrectly installed.
- Guidance on these areas can be found in Approved Documents, Part A1 and Parts K2 and K4 as well as Building Regulation 7.
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Are glass infill panels secured into place correctly using the appropriate number of fixings? Clipped panels with no bolts through the glass, should be supported on more than just the vertical edges. This will ensure appropriate support to the panel that matches the life of the balustrade.
i.e. For clipped infill panels – clips should be positioned around the periphery of the infill panel, at a maximum spacing of 600 mm. Each clip should be not less than 50 mm in length and should give a minimum depth of cover to the glass of 25 mm.
See also BS 6180:2011, Paragraph 8.4.4 for more detail.
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Check the appropriate loads are taken into account when designing balustrades as set out in BS 6180:2011, Table 2 and in the Eurocodes.
Typical minimum horizontal imposed loads for parapets, barriers and balustrades extracted from BS 6180:2011
| Type of occupancy for part of the building or structure | Examples of specific use | Horizontal uniformly distributed line load (kN/m) | Uniformly distributed load applied to the infill (kN/m2) | A point load applied to part of the infill (kN) |
|---|---|---|---|---|
| Domestic and residential activities | All areas within or serving exclusively one single family dwelling including stairs, landings, etc. but excluding external balconies and edges of roofs. | 0.36 | 0.5 | 0.25 |
| Offices and work areas not included elsewhere, including storage areas | Areas not susceptible to overcrowding in office and institutional buildings, also industrial and storage buildings. | 0.74 | 1.0 | 0.5 |
| Areas with tables or fixed seating | Restaurants and bars. | 1.5 | 1.5 | 1.5 |
| Areas without obstacles for moving people and not susceptible to overcrowding | Stairs, landings, corridors, ramps External balconies including Juliette balconies and edges of roofs. Footways and pavements within building curtilage adjacent to basement/sunken areas. |
0.74 | 1.0 | 0.5 |
| Areas susceptible to overcrowding | Theatres, cinemas, discotheques, bars, auditoria, shopping malls, assembly areas, studios. | 3.0 | 1.5 | 1.5 |
| Retail areas | All retail areas including public areas of banks/building societies or betting shops. | 1.5 | 1.5 | 1.5 |
A complete table of the load values can be found in BS 6180:2011.
Useful links
For further guidance as cited on this page, please click on the following links:
- Part A: Structure – Part A contains guidance on the structural stability and safety of buildings, from foundations to walls and roofs.
- Part B: Fire Safety – Part B contains guidance on fire safety, including means of escape, fire spread, structural fire protection and fire service access.
- Part K: Falling, collision and impact – Part K contains guidance on the safety of stairs, guarding, and glazing within and around buildings.
- Building Regulations – Regulation 7: Materials and Workmanship
- BS 6180:2011: Barriers in and about buildings – Code of Practice
- Eurocodes – The EN Eurocodes apply to the structural design of buildings and other civil engineering works.