New a test combination of ACM outer panel and non combustible insulation

More than 100 buildings have a cladding system that has failed the latest round of government combustibility tests, the Department for Communities and Local Government (DCLG) has said.

A total of 111 high-rise blocks use a combination of material that failed the second of six new tests rolled out at the recommendation of an independent expert safety panel following June’s Grenfell Tower fire.

The tests confirmed that a cladding system using aluminium composite material (ACM) panels with a polyethylene filler, and stone wool insulation “does not meet current building regulation guidance”.

Of the affected buildings, 90 are said to be local authority or housing association-owned or managed.

The new tests involve a nine-metre demonstration wall subjected to a replication of “a severe fire in a flat breaking out of a window” to see if the flames then spread up the exterior.

A statement from the DCLG said: “This wall system failed the test, which means it did not adequately resist the spread of fire over the wall to the standard required by the current Building Regulations guidance and which is set out in BR135.

“The expert panel’s advice is that, based on the test result, they do not believe that any wall system containing an ACM category 3 cladding panel, even when combined with limited combustibility insulation material, would meet current Building Regulations guidance, and are not aware of any tests of such combinations meeting the standard set by BR135.

“Wall systems with these materials, therefore, present a significant fire hazard on buildings over 18m.”

The government has commissioned the Building Research Establishment to carry out half a dozen tests into different combinations of cladding materials.