The shadow housing secretary, John Healey, told the House of Commons that “cladding is not the whole story”.
“The government is fundamentally flawed in its use of the BRE to conduct overly simplistic and limited fire test samples and not the complete cladding assembly,” said Stephen Mackenzie, a fire risk consultant. “The small scale tests on external panels need to to be extended to a full disassembly.”
He said he had observed the removal of panels in three locations, including in Camden, and said he was worried that “we could be pulling off cladding systems that are potentially OK”.
Tens of thousands of people are facing uncertainty over whether they will be able to stay in their homes and hundreds have already been evacuated from the Chalcots estate towers in north London.
Barry Turner, director of technical policy at Local Authority Building Control, which represents council building control officers also asked: “I would like to know just what tests these panels are failing.”
“For any material to undergo a fire test as laid down in BS476 [which grades fire resistance] or one of the EU equivalent standards, you need a specific panel size, it needs to be mounted in a specific way,” he said. “There are fire tests done on individual products, but you need to test them combined [including insulation, cavity and fire stops] to see if they meet performance criteria for the job as a whole. That is how these systems are assessed for compliance with the building regulations.”
One architect responsible for some of the projects where cladding has been ruled to have failed, asked: “What are they testing to what standard? This could be a massively costly and disruptive error to thousands of residents.”
On the Chalcots estate, the assembly is said to have been designed with the approval of building control and has been tested in two real fires, the latest in 2012, in which the fire did not spread beyond a single flat. This could have been because of the way the panels were combined with non-combustible mineral fibre insulation, fire breaks. Cutting off and testing a piece of the aluminium cladding would not tell the government’s testers anything about that wider context.
In Bootle, where two blocks had their cladding removed, the housing provider One Vision said: “Test results have shown certain elements of the cladding on two of our high-rise blocks, Cygnet House and Wren House, whilst meeting building regulations, does not meet the latest Department for Communities & Local Government test criteria.”