Green Wall Guidance

The Fire Protection Association has released a new set of guidelines, ‘Green and Living Walls as External Cladding: A Joint Guide to Managing Risk.’ As the title suggests, the guidance focusses on the risks associated with using plants as exterior cladding on the walls of buildings. In particular, the guidance considers the risks associated with fire, escape of water, and weather events and is targeted towards building designers, façade engineers, architects, product suppliers, owners, insurers, fire services, and those responsible for the safety of buildings.

The key points and challenges brought up by the guidance include:

• 19 core principles of risk control for living walls.
• The different types of living walls and how to maintain them.
• The risk of plant biomass combusting and the use of irrigation to mitigate this risk.
• The use of plastic in living wall designs and the risks associated with plastic burning and spreading fire.
• A current lack of guidance on managing fire spread between the living wall and the inside of the building through windows and vents.
• A lack of certification tests to address the specific fire challenges.
• The potential for living walls to cause mass fire spread over a building through both the plant surface and potting system.
• A lack of building regulations to address property protection.
• Potential structural damage to the building from water and wind.

The guidance also includes a questionnaire designed to gather key information about a proposed living wall and help consider whether there are risks that need additional consideration. The questionnaire is interactive and can be completed within the guidance.

Overall, the guidance highlights that most living walls are of a safe scale and in a location where they would not produce any additional risks that would require further action; however, those applied on a larger scale could have the potential to affect safety if not properly managed.