Key takeaways from BS 8579:2020

High rise building with balconies
High rise building with balconies

Here are some of the key takeaways from BS 8579:2020.

Definitions of terminology

In BS 8579:2020, the definition of a balcony has been revised to be extremely specific. A balcony is defined as an ‘Accessible external amenity platform above ground level, exterior to and with direct access from a building’.

BS 8579:2020 also clarifies the definitions of the following terminology:

Enclosed balcony – a balcony that is protected from rain ingress by a roof or balcony above and a wall(s) or weather screens to the sides.

Controlled drainage – drainage from a balcony that prevents water ingress to the interior, staining of the exterior of a building, and nuisance to people under or around the balcony or damage to the landscaping below.

Edge drainage – drainage of a water-collecting surface via the edge of a balcony.

In this latest update, certain new terms such as ‘principal water collection surface’, ‘ingress level’, ‘Juliet guarding’ and ‘weather screen’ have also been added and defined.

Structural and mechanical stability and integrity

BS 8579:2020 further talks about the structural and mechanical stability and the safety and integrity of balconies and terraces.

Balconies should be safe to install

In cases where they need to be installed using lifting equipment, balconies should be designed in such a manner that they do not require persons to be working underneath the suspended load. The design should also aim to reduce the number of persons working at height wherever possible.

Balcony design should promote safe maintenance.

When designing the balcony, the loads arising from the replacement of façade glazing or cladding adjacent to the balcony should be taken into account.

Need for soffits

Balcony design must make provisions to prevent liquids or solids falling onto occupants of the balconies below or into public areas. This can be managed by fitting a tray or impermeable layer into the soffit. Designers should assess the potential hazards of balconies above open pedestrian surfaces that do not have such protection and mitigate against injury.

Additionally, care must be taken to ensure that every part of the design, including soffits and fascia cladding, has physical fixings to prevent parts from becoming dislodged by wind, maintenance work or other factors.

Balconies should carry a warning regarding maximum loads

Every projecting or partially projecting balcony should incorporate a durable label or sign indicating the total safe imposed load for which the balcony is designed. Additionally, it should also warn inhabitants against the unsuitable placement of heavy objects, such as paddling pools, hot tubs and large planters, on the balcony.

This warning signage should be placed in a position permanently visible to the users, with instructions informing the inhabitants that it not be removed. The sign or label and its associated fixings should be designed to have a service life equivalent to that of the balcony.

Height of the balustrade

The balustrades of balconies need to be a minimum of 1100 mm high in all cases. However, where there is a step adjacent to the balustrade onto which it is possible to climb, the recommendation is that the balustrade height is 700 mm above that step.

Guard against wind uplift

Surfaces on which people walk surfaces and supporting layers should be properly affixed to ensure that they cannot be easily dislodged by wind, people walking on them or floatation. This should be ensured by adding sufficient weight to prevent their becoming dislodged.

Balconies should incorporate thermal breaks

Designers should ensure that balconies have suitable thermal breaks to reduce heat loss and avoid condensation risk. The potential for rotation, which can occur on balconies where the thermal breaks have a low spring value, should be taken into account.

Balconies must be slip-resistant

Slip resistance must be appropriate for the intended usage of the surface, taking into account the materials used and surface textures. Pedestrian surfaces should meet BS 7976 (all parts).

Fire issues that must be addressed

Balconies must

  • not be composed of a material or designed such that they provide a medium for undue fire spread over the external envelope of the building;
  • not propagate fire downwards, e.g. not produce falling brands or flaming/molten droplets or debris capable of initiating fire below;
  • be designed so as to minimise the risk of them becoming detached from the face of the building and presenting a hazard to people below, e.g. firefighters or the public;
  • be designed to minimise the risk of prejudicing the stability of the building when undergoing large deformations resulting from fire exposure.

Drainage requirements

Balconies and small terraces should be designed to include some kind of controlled drainage that prevents water ingress into the building, staining on the building, and nuisance to people or the landscaping below. Either edge drainage or pipe drainage could be employed to ensure that there is no water ingress.

The recent changes in the fire safety regulations for external walls have led to a series of refurbishments in residential buildings over the height of 18m. These include buildings in the social, private and public residential sector. The government also allocated a fund to help various buildings in the private sector deal with the costs of refurbishment. But despite the additional funds, there has been a significant slowdown in the rate of refurbishment. 

According to a recent survey conducted by the Building Safety Register, one-third of the landlords expect the process of refurbishment to take over two years. The poll results of 1048 high-rise building landlords from both the social and private sector revealed that they would require over 25 months to ensure that their building was in compliance with the latest regulations in the Building Safety Bill. 

The bill that was introduced in July contained various changes to the current building safety laws, specifically pertaining to the external wall systems of buildings. The bill also introduced a new regulator to regulate landlords and impose sanctions on those found to be in breach of the various newly introduced safety standards. This position was introduced to ensure that building safety standards were being met. 

The survey found that the respondents were being faced with multiple issues which were responsible for slowing down the refurbishment rate. These issues included the absence of clarity, the complexity of the processes, competing for organisational priorities and the need to submit to a new regulator due to a high volume of high-rise buildings. 

Additionally, the resulting costs of the refurbishment was also a major issue for many landlords. The poll revealed that 45% of the landlords said that the bill would have a significant negative impact on the organisations’ finances whereas 33% voted that the impact would be moderately negative. 

About 56% of the respondents of the survey had less than 20 high-rise buildings in their portfolio. 33% of the others had between 20 to 150 whereas 11% had more than 150. 

Further in the ‘Building a Safer Future’ consultation, the government also asked organisations to identify ‘duty holders’ who would be deemed responsible for the fire and structural safety risks in buildings. These appointed duty holders would be responsible for creating a special safety case which would contain all the essential and relevant information on fire and structural safety risks for each building under them. In the poll conducted, no landlord could provide an estimate for the average cost that would be incurred for producing this required ‘building safety case.’

To find out more about the legislation and the requirements for non-combustibility on external facades why not book one of our CPD’s