Risk management of living and green walls

The RISC Authority has recently published its guidance on the management of fire, weather and escape of water risks presented by living and green walls.

The guidance has been written to ensure that appropriate interested parties, such as insurers, fire authorities or building control, are informed of proposed designs of living and green walls, and are able to identify whether special risk considerations are required. The main risk elements of living and green walls include:

• Combustibility of the planted biomass and its dependency on irrigation and maintenance to keep ignition and fire spread potential to a minimum
• The extensive use of plastics in some Living Wall designs in the potting, irrigation, and drainage systems
• The potential complexity of creating a fire-safe design when incorporated into a rainscreen type cladding system
• A lack of guidance on the management of penetrations (windows and vents) to prevent fire ingress or egress between the building’s internal compartments, wall voids, and the living wall
• A lack of relevance of some certification tests to address the fire challenges
• The potential for the aforementioned factors to allow mass fire spread over the building, both via the planted surface, and within wall cavities behind the potting system
• The potential for water and wind damage

The guidance document is split into two sections: Living Wall Questionnaire; and Background Information and Guidance. The guidance section consists of the following sections:

• Types of living wall
  Living walls, stakeholders and building/business resilience
  Core principles of risk control for living walls

A free copy of the guidance is available here.

Further guidance on Construction risks is available from Griffiths & Armour. For further details and support, please get in touch.