This section looks at the regulations and requirements which your need to know, and consider when working on balcony designs.

1. Deflection/Structural Requirements

Balconies need to meet two requirements from a deflection and structural perspective.

a. BS/EN Standards. Including BS 5080-1,2:1993 & BS EN 1090 & BS EN 1990:2005

b. CE Marking. Read BS EN 1090. Typically buildings require EXC 2 compliance.

2. Thermal/Environmental Requirements

a. Thermal Bridging. See Part L section 1 A. See BRE Information Paper IP/06 106. Thermal performance must consider entire buildings. Ensure all components with a thermal role work synergistically. Bet a balance between thermal and structural performance.

b. Sustainability. Conduct visual checks periodically. Design with maintenance in mind. Avoid single drainage outlets. Drip tray inspection is advised.

c. Lifespans. Balconies are one of the few structural elements exposed to weathering. Lifespan duration depends on maintenance and mid-life replacement. CAB say the recycling rate for architectural aluminium is 92-98%, as only 5% of the original energy is required to recycle it. 

3. Balustrade Guidance

a. Approved Document Part K indicates a balustrade should be 1100mm high, 100mm sphere should not be able to pass through the balustrade, avoid using midrails, safe breakage and glazing sizes.

b. BS6180:2011. Is the main Standard affecting balustrade design. 100mm sphere should not be able to pass through the balustrade and should not easily be climbed.

c. Use of glazing. Common benefits of using glazing are; its relatively low cost, low maintenance/long life span, high impact resistance and strength, wide range of colour and obscurity options, creates openness and enables views, can easily be printed or customised, and easily customisable and easy to process.

d. CDM regulations. It is essential to know what the replacement strategy is and how this affects your design.

4. Fire Requirements

a. Approved Documents Part B July 2019. Balconies are now regarded as part of the external façade, and the regulations regarding use of non-combustible materials should be applied. This means that any balconies located within 1m of a relevant boundary, or located  more than 18m above ground level, must be entirely formed from non-combustible materials.

b. Combustible Cladding Ban. The “Combustible Cladding Ban” is the Amendment to the Building Regulations that came into force on 21st December 2018. Banning the use of combustible materials in external walls of high rise buildings above 18m. 

c. Advice Notes. Building owners should be aware of the materials used in the construction of ..balconies  (regardless of height) and the potential for any horizontal and vertical fire spread due to their arrangement on the external wall.

d. BS EN (Fire class requirements). This regulation outlines the test method which should be used on balconies expected to become fully engulfed in fire ( a rare occurrence) , however as can be seen above there is no current requirement for these tests to be carried out on residential balconies.

e. Mandatory Handbook in Scotland. The regulations, set to come into effect on 1st October will bring the threshold of the combustible cladding ban down from 18M and above, to 11M. Additional escape stairs and storey identification signs will also be required to aid fire and rescue services to navigate buildings in the event of an evacuation.

Project Specific Additional Requirements

5. Insurance/Warranty Provider’s Requirements

a. Level thresholds. NHBC states door sills must project a minimum of 45mm along with a maximum upstand of 15mm at the door threshold.

b. Drainage. See NHBC Standards, chapters 7.1 & 7.2. Balconies over 6m2 must be drained. Water management should be considered for all balconies. – 

c. Decking. Minimum 10mm gaps hould be provided between individual units of decking or paving. Spacers and supports which raise decking or paving should not obstruct the flow of rainwater to outlets. 

6. London Housing Design Guide

Balconies should be a Min 5 sq m for 2 people + 1 sq m per additional occupant. Min 1500x1500mm space. Level, watertight threshold at max 15mm height. Consider privacy, shelter and “Secured By Design”.

7. Lifetime Homes

16 Lifetime Homes design criteria. Meeting Lifetime Homes ensure Part M compliance. Criterion 15 glazing & window handle heights. Principle glazing to have 400mm min height difference between balustrades and cills, etc.

A clear width of 1500mm for turning circle is required.

For a comprehensive guide on all the BS EN standards which effect balcony design, head to