Last edited 13 Jan 2019

Limited combustibility

In England, the building regulations establish requirements for specific aspects of building design and construction. Approved documents then provide guidance for satisfying those requirements in common building situations.

Approved document B of the building regulations 'Fire Safety', defines limited combustibility as: 'A material performance specification that includes non-combustible materials, and for which the relevant test criteria are set out in Appendix A, paragraph 9.'

Requirements for materials of limited combustibility are defined in table A7 of Approved Document B.

Approved document b table a7.jpg

Following the Grenfell Tower Fire, a decision was taken to ban combustible materials in the cladding for buildings over 18m in height. The following change to approved document 7 came into force on 21 December 2018.

The Building Regulations restrict the use of combustible materials in the external walls of certain buildings over 18m in height. Refer to regulation 7(2) of the Building Regulations and to Approved Document B: volume 2, part B4 for details.

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