Hearings focused on the degree to which cladding manufacturer had misled customers over its ACM panels

“Deliberate concealment” is how Grenfell Inquiry barrister Richard Millett QC described materials manufacturer Arconic’s marketing of its combustible ACM cladding.

The accusation was a central theme in this week’s evidence at the inquiry, which focused on the degree to which Arconic knowingly misled its customers on the fire safety of its combustible Reynobond PE cassette cladding panels.

The firm sold 3,000sq m of the cassettes to the team working on the refurbishment of the Grenfell Tower – cladding which, along with other materials produced by Kingspan and Celotex, has been found to be the “primary cause” of the disastrous fire in June 2017 which claimed the lives of 72 people.

But the cassettes had “disastrously” failed a fire test in 2005, resulting in a fire safety rating – Euroclass E – which outlawed its use on buildings taller than 18m in the UK. 

Despite the failed test, staff at the firm continued to market the product, supplying customers with test results of a different version of the cladding which had passed.

They also failed to tell the UK regulator, the British Board of Agrement (BBA), despite Arconic’s contract with the regulator requiring that all available test data be supplied.

Claude Schmidt

Arconic president Claude Schmidt giving evidence to the inquiry this week

Yet, during Wednesday’s hearing, Arconic president Claude Schmidt refuted Millett’s accusation of deliberate concealment, saying that it was “too much”. According to Schmidt, the data “could have been found out, discovered, during an audit”.

Millett then suggested that Arconic’s failure to tell the BBA about the failed test of the cassettes was a “misleading half truth”, a description which Schmidt was more comfortable with. “Yes, you can see it like that,” he replied.

The evidence presents striking parallels with that given by materials manufacturers Celotex and Kingspan last year. 

The inquiry heard before Christmas how Celotex had rigged a 2014 fire test of its RS5000 insulation – which was installed on Grenfell Tower for its refurbishment – by adding extra components to the test rig to ensure a pass.

It was also revealed that the product, which was marketed as safe to use on buildings above 18m, was actually the same as an earlier insulation which had failed the fire test for buildings of this height.

Additionally, it was revealed last year that for more than 14 years Kingspan had been marketing its K15 Kooltherm insulation – also installed on Grenfell tower – as safe for use above 18m on the basis of a fire test from a different product.

Kingspan only withdrew the new version of the insulation, which the inquiry heard turned a 2007 test rig into a “raging inferno”, from the market in October last year after admitting it was “now of the view” that the product for sale was different to what had been tested.

Meanwhile, Arconic had tested two versions of its Reynobond PE cladding panels, which both contained a combustible plastic core composed of 100% polyethylene.

The first had been on a riveted form of the product, which had resulted in a Euroclass B rating, allowing it to be used on the external walls of high-rise buildings.

The second test was on a folded version, known as cassettes, which the inquiry heard had “performed disastrously”, releasing seven times more heat and three times as much smoke as the riveted version.

Technical staff at the firm had been “puzzled” by the results, according to the witness statement of then-technical manager Claude Wehrle.

“No one really understood it,” Wehrle said. “Competitors were not exhibiting any problems and no one in the industry seemed to have similar results insofar as I could tell”.

Wehrle claimed that the results led staff to believe that the test was a “rogue” result as the firm had a “general view” that the riveted panels would perform better in a fire test than the cassette form.

Because of this assumption, Wehrle said that the marketing, technical and management teams “decided at the time that a classification in category B was satisfactory” and had not considered carrying out further tests.

Schmidt admitted on Tuesday that this decision was, in the words of inquiry chairman Martin Moore-Bick, “irrational and irresponsible,” and added that more tests should have been carried out.

Asked by Millett if the claim was a lie, Schmidt agreed that it was

But Wehrle’s claim that staff believed the test on the cassettes was a “rogue” result was also put under scrutiny this week.

Schmidt was shown an email referring to the cassette’s fire performance in which Wehrle said: “This shortfall in relation to this standard is something we have to keep as VERY CONFIDENTIAL!!!!”

Asked by Millett if the email showed that Wehrle “knew very well that the [cassette test] was not a rogue”, Schmidt agreed.

Millett then asked: “Do you accept that Arconic, through Mr Wehrle, knew that such people − architects, designers, construction professionals − were being misled by the claimed fire certification for cassette?” Schmidt replied: “Yes.”

Thursday’s hearing was also shown email exchanges in 2010 between Wehrle and then-sales executive Isabel Moyses, who had been asked by a customer to supply the test data for the Reynobond PE cassettes.

Wehrle replied: “It’s hard to make a note about this… Because we’re not ’clean’…”

Wehrle then emailed the client claiming the successful test of the riveted version covered the cassette type, as the riveted was the “worst case” of the product.

Asked by Millett if the claim was a lie, Schmidt agreed that it was.

Vince Meakins

Arconic sales manager Vince Meakins said he had never been warned about the firm’s PE cladding panels

Arconic continued to sell both versions of its Reynobond panels through to 2017 and only ceased production on 26 June that year, 12 days after the Grenfell Tower fire.

This is despite the firm ordering its French sales team to stop selling the products in France more than a year before the fire, and instead to sell only a more fire-resistant version called FR.

In emails shown to Monday’s hearing, French sales director Alain Flacon told the firm’s French sales team: “In view of the potential calorific [fuel content] benefits of Reynobond FR (vs Reynobond PE), and consequently its superior performances, we have taken the proactive habit of favouring FR as the only solution in our specifications.” 

The email then continued in bold text: “As from today, I ask you to go even further and to systematically confirm in writing the requirement for FR for all projects on which a Reynobond specification is involved, regardless of the nature and size of the building project.”

It was a warning which UK sales manager Vince Meakins said he was never given.

Reynobond PE was the most popular of Arconic’s cladding products in the UK at the time, with the inquiry hearing that it was sold “by default” over Reynobond FR, which cost around €4 to €5 per sq m more than Reynobond PE.

The inquiry continues.