External Timber Cladding and Fire Risk
Guidance to Amended Building Regulations
Recently published amendments to Approved Document B of the Building Regulations confirm that, in buildings with a ‘residential’ purpose and a storey of 11m or more in height, elements such as cladding, balconies, and other external surfaces must achieve class A1 or A2-s1, d0.
While some exemptions apply, this effectively bans the use of combustible materials for these elements.
Timber cladding is still approved for most non-residential buildings and for all those under 11m in height, often with the added protection of flame retardant treatment.
For ‘RELEVANT’ Buildings (residential multi-storey 18m+)
No timber cladding on buildings over 11m, but you can use timber within the external wall structure up to 18m.
No timber in external walls on buildings above 18m – this affects external wall framing/CLT and cladding.
Other Buildings (non-residential other than domestic housing)
No change to before – timber cladding can be used, normally with Flame Retardant (FR) treatment, up to and beyond 18m
These changes to the Building Regulations will come into force on 1 December 2022.
To reflect these changes and guide members through the implications for their business, the WPA has updated Guidance Note FR5: External Timber Cladding and Fire Risk – Guidance to Amended Building Regulations.