The specification of combustible insulation for the walls of Grenfell Tower was an “ongoing and major failure” by the project’s architects, which a reasonably competent professional should not have made, an expert witness to the inquiry said today.
Paul Hyett, a former president of the Royal Institute of British Architects engaged to provide an expert assessment of Studio E’s work on the tower, told the inquiry today that the architects were wrong to assume that the insulation used on the tower was acceptable.
Celotex FR5000 (later switched for an equivalent product with the different branding RS5000) was specified by Studio E in 2013, after being suggested by engineering consultantcy Max Fordham.
In his evidence, lead architect Bruce Sounes explained that he had “made an assumption” that the products complied with rules because Max Fordham had “used this before in similar circumstances”.
But Mr Hyett said this was not a good enough reason to assume that the product was acceptable. “They should have already known [that it was not acceptable] or they should have investigated,” he said. “I think it’s reasonable to be pretty disappointed that a recommendation has been made, but they had a responsibility to check it… I’m clear that the final responsibility for this lies with the architect.”
The Celotex insulation was made of polyisocyanurate, a plastic that burns in a fire and releases large quantities of toxic smoke, including cyanide. It was banned under guidance unless justified by a large-scale test of the entire system in which it was used.
In a section of his report, shown to the inquiry, Mr Hyett wrote: “Studio E’s continued confidence in the Celotex RS5000 product… represents an ongoing and major failure on their part to understand both the requirements of the building regulations and the guidance.”
Mr Hyett earlier said that it was Studio E’s responsibility to check the compliance of products before including them in specification for the work, before it was tendered to a contractor.
He said that while the contractor – appointed on a design-and-build basis – also should have carried out its own checks, this did not “absolve” Studio E of responsibility.
Mr Hyett was also asked extensively about a certificate for the aluminium composite material (ACM) cladding panels produced by the British Board of Agrement (BBA) – a respected certifying body – which said that they “may be regarded” as having a Class 0 surface.
He said that he believed it was reasonable for the architects to have taken this as evidence that the panels met the requirement in Approved Document B that the external surfaces of walls are required to be Class 0.
“What I’m absolutely clear about is that the architect needs to establish in context of this product [ACM] that it carries the correct certificate,” he said. “That needs to be established somewhere reliable and the fallback is the BBA certificate and that’s where I would go.”
However, pressed on his claim that it was reasonable for the architects to read no further than the first page of this certificate, he accepted under questioning that this argument “does not stand”.
The rest of the document contained a number of disclaimers – including the fact that the panel was available in a fire-resistant version, that colour changes could affect its fire performance, and limits to the testing that supported its Class 0 rating.
Earlier Mr Hyett also said he was not persuaded by Studio E’s argument that all they were required to check design drawings for was “architectural intent” – by which they meant the correct aesthetic.
He said they should have been ensuring that sub-contractor Harley Facades had “properly understood and applied” the designs from Studio E, including the fact that they were compliant.
The inquiry continues with further evidence from Mr Hyett tomorrow.
Week one: A vivid picture of a broken industry
After a week of damning revelations at the opening of phase two of the Grenfell Tower Inquiry, Peter Apps recaps the key points
Week two: What is the significance of the immunity application?
Sir Martin Moore-Bick has written to the attorney general requesting protection for those set to give evidence at the Grenfell Tower Inquiry. Peter Apps explains what the move means
Week three: Architects of misfortune
This week saw the lead architects for the Grenfell Tower refurbishment give evidence to the inquiry. Peter Apps runs through the key points
Week four: ‘I didn’t have any perception that it was the monster it’s become’
The architects continued to give evidence this week, outlining a lack of understanding of the fire risk posed by the cladding materials and its design. Nathaniel Barker reports
Week five: ‘No adverse effect in relation to external fire spread’
As the Grenfell Tower Inquiry returns from its long absence, Peter Apps recaps the key points from a week of important evidence from the fire consultants to the refurbishment
Week six: ‘I can’t recall any instance where I discussed the materials with building control’
Nathaniel Barker summarises what we learned from fire engineers Exova, architects Studio E and the early evidence from contractor Rydon
Week seven: ‘I do not think I have ever worked with a contractor operating with this level of nonchalance’
Two key witnesses from contractor Rydon gave evidence this week. Peter Apps recaps some of the key points from a revealing week of evidence
Week eight: ‘It haunts me that it wasn't challenged’
Four witnesses from contractor Rydon gave evidence this week. Lucie Heath recaps what we learned on the last week of evidence before the inquiry breaks for five weeks
Week nine: ‘All I can say is you will be taken out for a very nice meal very soon’
This week the inquiry heard evidence from witnesses at Harley Facades, the sub-contractor responsible for Grenfell Tower’s cladding. Peter Apps recaps the key points
Week 10: ‘As we all know, ACM will be gone rather quickly in a fire!’
As the Grenfell Tower Inquiry entered its 10th week, Jack Simpson recaps the key points from a week of important evidence from the refurbishment’s cladding contractor
Week 11: ‘Did you get the impression Grenfell Tower was a guinea pig for this insulation?’
With witnesses from the cladding subcontractor, the firm which cut the deadly panels to shape and the clerk of works which inspected the job giving evidence this was week full of revelations. Peter Apps recaps the key points
Week 12: ‘Would you accept that was a serious failing on your part?’
With the surveyor who inspected Grenfell Tower for compliance giving evidence, this was a crucial week from the inquiry. Dominic Brady and Peter Apps report
Week 13: ‘Value for money is to be regarded as the key driver for this project’
With consultants to Kensington & Chelsea Tenant Management Organisation (KCTMO) giving evidence, attention at the Grenfell Tower Inquiry turned for this first time to the actions of the TMO and the council. Peter Apps reports
Week 14: ‘Did it not occur to you at this point that your budget was simply too low?’
This week, for the first time in phase two, the inquiry heard from Kensington & Chelsea Tenant Management Organisation, the landlord that oversaw the fatal refurbishment of Grenfell Tower. Lucie Heath reports
Week 15: ‘Have you ever informed the police that you destroyed documents relevant to their investigation?’
Witnesses from the Kensington and Chelsea Tenant Management Organisation (KCTMO) gave evidence for a second week, which began with a shocking revelation about withheld and destroyed evidence. Pete Apps recaps
Week 16: ‘I conclude this was very serious evidence of professional negligence’
This week saw members of Kensington & Chelsea Tenant Management Organisation finish giving evidence, before the inquiry’s expert witnesses took the stand to make some highly critical assessments of the work they had seen before and during the refurbishment of Grenfell Tower. Jack Simpson recaps
Week 17: ‘It’s hard to make a note about this because we are not clean’
The start of the second module of the Grenfell Tower Inquiry phase two came with some huge revelations about the companies that sold the products used in the cladding system. Peter Apps reports
Week 18: ‘It was just reckless optimism wasn't it?’
As the inquiry began cross-examining witnesses for the second module of its phase two work, the picture surrounding just how Grenfell Tower ended up wrapped in such dangerous materials became a little clearer. Nathaniel Barker was keeping an eye on proceedings
Week 19: ‘And that was intentional, deliberate, dishonest?’
The Grenfell Tower Inquiry this week heard the shocking story of how the insulation manufacturer "manipulated" official testing and marketed its product "dishonestly". Peter Apps tells the story
Week 20: ‘We were outed by a consultant who we then had to fabricate a story to’
This week the inquiry investigated the actions of Kingspan – the manufacturer of one of the insulation products used in the tower’s cladding system. Dominic Brady reports
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