Taken from the minutes of the CWCT Fire Group meeting minutes, held on 2 July 2014, which government officials attended

Use of ACM on high rise buildings

"ACM refers to aluminium composite material. The normal material consists of two skins of aluminium approx. 0,5mm thick separated by a polyethylene core 2 to 5mm thick. This material generally achieves a reaction to fire classification of class 0 or class B s1 d0. There are versions available with a mineral core which can achieve A2 s1 d0. There are also similar materials available with other metals such as copper used for the facing.

"There have been major fires in buildings in various parts of the world including the Middle East and France where ACM materials have been used for the cladding with the ACM responsible for external fire spread.

"It was stated that clause 12.7 of ADB is intended to prohibit the use of polyethylene cored ACM in buildings over 18m as they are not classed as limited combustibility.

"This is not clear from the wording of the current clause. The current clause is preceded by a heading ‘Insulation Materials/Products’ which implies that it only applies to insulation. The wording of the main text refers to filler materials which could be taken to include the polyethylene core but this is not clear.

"It was suggested that clarification could be achieved by means of a FAQ. Approved Documents can be downloaded from www.planningportal.gov.uk. The page for each Approved Document also has a FAQ section related to that Approved Document. [a representative from the BRE] agreed to raise this with [an official at the Department for Communities and Local Government]"

Square brackets indicate redacted names, which have been confirmed through sources. The full minutes can be downloaded below.