To ask the Secretary of State for Housing, Communities and Local Government, if he will set out where in the building regulations or guidance issued by his Department before the Grenfell Tower fire it was made clear that the limited combustibility requirements in the guidance covered the core filler of a cladding panel.
Requirement B4 of Schedule 1 to the Building Regulations 2010 requires that the external walls of a building shall adequately resist the spread of fire over the walls. This provision has been in place since 1985. The approved document gives guidance on how these requirements may be met. Paragraph 12.5 of Volume 2 of Approved Document B sets out that the external envelope of the building should not provide a medium for fire spread if it is likely to be a risk to health and safety. The provisions relating to limited combustibility in paragraph 12.7 of the Approved Document B have, since the version published in 2006, included references to insulation products, filler material etc.