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The following BSI references relate to the work on this document:
Committee reference B/209
Draft for comment 20/30380151 DC

Foreword

Publishing information

This British Standard is published by BSI Standards Limited, under licence from The British Standards Institution, and came into effect on 31 August 2020. It was prepared by Technical Committee B/209, General building codes. A list of organizations represented on this committee can be obtained on request to its committee manager.

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Introduction

The UK has seen an increase in medium and high-rise residential development in cities. The need to provide outdoor amenity space for occupants in apartments gives rise to the proliferation of balconies and roof terraces. Industry is frequently divided in opinion about the design of balconies and terraces. The need for a guide has therefore been identified to provide better guidance for harmonizing the drivers of safety, longevity, inclusive access and weathering.

This British Standard aims to set a benchmark for quality and functionality in the design of balconies and terraces.

1 Scope

This British Standard gives guidance on the design of balconies and terraces and their component parts.

Balconies and terraces covered within this British Standard can be at any height above lowest ground level, unless stated otherwise.

This British Standard defines Juliet guardings but covers their guarding elements only.

Certain aspects of this British Standard are not applicable to walkways, roofs, pedestrian surfaces and balconies intended for access only for maintenance. These include enclosure of balconies, arrangement of balconies, wind effects, inclusive design, safety (other standards apply), ventilation outlets and acoustic design. This British Standard is not specifically intended to cover internal balconies, such as within a building atrium or covered courtyard, but relevant guidance herein can be used in the absence of guidance specific to such balconies.

Asset protection other than service life is not included within the scope of this British Standard.

Raised timber structures on support posts built into the ground and serving ground floor accommodation are considered raised pedestrian surfaces and outside the scope of this British Standard.

2 Normative references

3 Terms and definitions

4 General principles

4.1 General

4.2 Relationship of balconies to the building

5 Enclosure of balconies and small terraces

5.1 General

5.2 Daylight, thermal, ventilation and acoustic considerations

5.3 Drainage considerations

5.4 Fire considerations

5.5 Finishes and equipment

6 Arrangement of balconies

6.1 Proximity and organization of multiple balconies

6.2 Level above ground

6.3 Privacy

7 Wind effects

7.1 General

7.2 Wind mitigation measures

8 Service life of balconies with a floor level greater than 2.4 m above ground level

9 Inclusive design

9.1 Thresholds

9.2 Balcony and terrace dimensions

9.3 Balcony and terrace surfaces

9.4 Sight lines via balconies and terraces

10 Structural and mechanical stability and integrity

11 Safety

11.1 Persons occupying the balcony or terrace

11.2 Persons below the balcony or terrace

11.3 Persons constructing, cleaning, maintaining and dismantling

12 Performance in fire

12.1 General

12.2 Materials and components for balconies in respect to fire

12.3 Materials and components for terraces in respect to fire

13 Thermal considerations

13.1 General

13.2 U-, ψ- (psi) and χ-(chi) values

13.3 Coupling and transmission heat loss coefficients

13.4 Condensation risk

14 Ventilation outlets near balconies and terraces

15 Weathering and hydraulic design

15.1 General

15.2 Drainage of balconies and small terraces

15.3 Drainage of large terraces

15.4 Prevention of water ingress into the building

15.5 Managing water drainage

15.6 Edge drainage of balconies and small terraces

15.7 Assessing the volume of rainfall on balconies and terraces

15.8 Pipe and outlet design

15.9 Prevention of surface staining

16 Security

17 Acoustic design

17.1 General

17.2 Balcony position on a facade

17.3 Enhancement with acoustic absorption or diffusion

17.4 Location of ventilation opening within balcony design

17.5 Enclosed balcony design for acoustics

17.6 Integration within acoustics, ventilation and overheating design

Bibliography

BS 8579:2020

Guide to the design of balconies and terraces

Current

Published:

31 Aug 2020