This week the Grenfell Tower Inquiry heard its first witnesses from the Building Research Establishment – the testing house that carried out key fire tests on the Kingspan and Celotex insulation products later used on Grenfell Tower. Peter Apps reports
It is necessary to begin with some explanations – and a little history.
For 80 years, the BRE was the country’s national centre for research into building science, but in 1997 it was privatised. Since then it has been required to win work from commercial clients and bid for government research contracts to secure its income.
In 1999, amid a parliamentary investigation into two cladding fires in the 1990s, it proposed the use of large-scale fire tests that mimicked real-world building facades as a means of deciding whether a certain construction build-up was safe.
But the BRE would be paid to run these tests (a before/after image from one is shown above).
Richard Millett QC, lead counsel to the Grenfell Inquiry, asked Phil Clark, the week’s first witness: “Was it the goal to use the test to BRE’s commercial advantage?”
Mr Clark replied that it was not, emphasising that the tests could have been carried out by “anyone in the world”.
The testing methodology was then written into a formal British Standard (BS 8414) in the 2000s and official guidance was amended so that passing one of these tests was recognised as a means to use systems with combustible materials on high-rise buildings.
Brian Martin, a BRE employee, was seconded to government to work three days a week developing this.
“Would it be fair, from your own knowledge, to describe BS 8414 and BR 135… as a joint project as between the BRE on the one hand and government on the other, with Brian Martin on both sides?” asked Mr Millett.
Mr Clark agreed that it was. Mr Martin was eventually employed full-time by the government, where he remains a key civil servant.
Both Celotex and Kingspan went on to undertake multiple tests at the BRE’s facilities. It is the Celotex tests to which we will turn first.
Celotex carried out the first test on a system containing its RS5000 insulation in February 2014, resulting in a failure.
The inquiry was played footage from the helmet camera that Mr Clark (pictured above) wore during this test, and it showed him giving a running commentary of what was happening to the Celotex representatives present.
He explained that the cladding panels falling away had left the cavity barriers with “nothing to push against” and told them that he had “seen worse” failures. The problem is, he should not have been offering any advice.
“Just looking at all of that, that’s advice, isn’t it?” Mr Millett said. “It’s the benefit of your experience that you’re imparting to the client, isn’t it?”
Mr Clark denied this, saying that it was merely “passing on information as to what was seen and how things behave”.
Jonathan Roper, one of the Celotex witnesses, has claimed that Mr Clark advised him that thickening the external cladding panels may help achieve a pass on the second attempt. Mr Clark said he could not recall such a conversation taking place.
Celotex passed its test at the second attempt in May 2014. But this test used secret additional magnesium oxide boards to strengthen the cladding panels – a feature declared neither in Mr Clark’s test report nor in Celotex’s later marketing of its product.
Much of the cross-examination focused on whether or not Mr Clark knew that these panels were present. Two Celotex witnesses – Mr Roper and his colleague Jamie Hayes – have said they have “no doubt” that he knew. But Mr Clark vociferously denied this.
The magnesium oxide boards were hidden behind cladding panels of a different thickness – 8mm rather than 12mm. They were also a different colour (the orange strips on the picture below).
Mr Clark claimed that he thought all the panels were 12mm thick and the colour change was simply a result of “supply shortages”. But he did sign a delivery note specifically indicating that they were 8mm thick, a detail he claimed not to have noticed.
However, there was no delivery note found for the magnesium oxide board. Mr Clark said it “may have got lost” as security guards sometimes delivered materials directly to the burn hall.
“Does that mean that when you conducted a test, you weren’t always absolutely sure what the precise make-up and composition of the rig you were testing was?” Mr Millett asked.
“I wouldn’t say necessarily, no, but if you’ve got somebody who’s going out of their way to deceive, then there was a possibility they could do that,” Mr Clark replied.
A number of things were not done according to procedure for the May 2014 test.
These included a lack of any revised drawings from the February test – despite the change in cladding panel.
And a requirement to photograph every component before it was placed on the rig was not met.
Mr Clark said that he was out of the office on a first aid course when the test rig was assembled and that it was overlooked by “whoever was deputising for me”.
Asked why he did not see the magnesium oxide boards being placed on the rig, he insisted that he “wasn’t in the office when it was being done”.
“Somebody at the BRE must have seen it being applied, though, mustn’t they?” asked Mr Millett (pictured above).
“I think they would have done, yeah, somebody should have done, but nobody had pointed it out to me,” Mr Clark answered.
The boards were visible in photos taken of the fully constructed rig (below). But Mr Clark claimed never to have seen these photos before giving evidence this week. He said they may have been taken by an apprentice who missed the significance.
“This is quite an incredible list of omissions and missed instances, isn’t it?” Mr Millett asked.
“Yes, I probably agree with you, yes,” Mr Clark replied.
“I mean, Mr Clark, isn’t the reality that you knew very well that there was a 6mm magnesium oxide layer behind it? You were in charge of this test, the photographs showed it was there, the deputy knew it was there… and it was covered over by a perfectly obvious ruby-coloured band in two places of a material of a different thickness. Surely you must have realised what was behind it?” Mr Millett said.
“No, I would have reported it. And had I known it, I would have stopped the test,” Mr Clark stated.
Helmet camera footage of the test compounded this line of questioning. Mr Clark was filmed making comments that referred to the boards, according to Celotex witnesses.
These included him saying “see how that flame seems to have ceased now that the board is there”, and “sometimes changing two things at a time doesn’t always give you an advantage”.
For the former comment, he said that the word “boards” was merely a reference to the external cladding panels and his use of the word “now” was no more than “misuse of a word” in “general conversation”.
For the latter, he was asked why he said “two things” had changed, when he was supposedly aware of only one change (the increased thickness of the panel).
He said he was simply explaining “the scientific principle that if you change two variables you don’t always know which has had the effect”.
Mr Millett said: “I’m going to put it to you squarely, Mr Clark. This was not just the imparting of a scientific principle, it was a reflection of the fact that you knew two things had been changed.”
“No, I refute that,” Mr Clark replied.
Finally, when writing up his test report, which made no reference to the boards, Mr Clark included an image – below – that plainly shows the magnesium oxide boards being removed from the rig. Celotex specifically asked him to remove this image – a request he denied.
Asked why he did not notice the boards in this photo, Mr Clark said: “In hindsight, probably, yes, I would − I should have picked up on it, but what you need to appreciate is at any one time I could have had seven or eight projects I was working on on my desk to write reports for.”
“That’s not credible, is it, really?” Mr Millett said.
Mr Clark denied this, saying he had “a very busy, high-pressured job”.
In the course of making these denials, Mr Clark claimed not to have had access to any documents other than those sent to him by the BRE.
However, this claim was subject to a denial by the BRE’s lawyers, who said he had been given three days’ unsupervised access at the BRE’s offices in order to access any documents he needed to prepare his statement.
“I’m putting it to you that you have given false evidence to the inquiry about this,” said Mr Millett.
“It’s not false evidence… I had forgot, when you were asking the question, that I had been there,” Mr Clark responded.
With regard to Kingspan, Mr Clark was mainly asked about a test in March 2014 that paired the firm’s K15 insulation with high-pressure laminate cladding panels.
This test was a failure due to flames exceeding the top of the rig (pictured above), but serious questions were posed about the way both Mr Clark and Kingspan went about it.
First, it transpired that Mr Clark did not immediately terminate the test when the flames passed the top of the rig, despite an unambiguous requirement to do so in the testing rules.
Mr Clark explained this by saying it was common practice at the BRE to allow clients to get “as much learning as possible” from the test data.
Helmet camera footage from this test then showed Mr Clark writing notes recording that the flames had passed the top of the rig, and Kingspan’s Ivor Meredith saying: “Can’t you just delete the whole sentence?”
Mr Clark replied: “I will put…” before trailing off.
“It looks from this that you were writing your notes in collaboration with Mr Meredith?” Mr Millett asked.
“There was no collaboration in any way, shape or form,” Mr Clark replied, adding that if he had anything to hide he would not have worn his helmet camera.
After the test was deemed a failure, Kingspan complained and asked for it to be regraded as a pass.
The BRE declined, but Mr Clark was asked to write a report for the test anyway. This was unusual – emails show him refusing to do so on other occasions.
“I don’t think I was very comfortable with issuing one,” he said, adding that he did not ask why he was being asked to provide the report.
Asked by Mr Millett if “very great care would need to be taken” in writing the test report to ensure it was not misconstrued as a pass, Mr Clark said yes.
But he added: “I think the test report doesn’t necessarily, unless you thoroughly read it, make it clear that the system has failed.”
In fact, the report made only a simple reference to the fact that flames passed the top of the rig after 43 minutes, in a timeline of events.
Subsequently, Kingspan used the report as evidence for reports written by fire consultancies to approve an untested system for use on a high rise (known as a desktop study).
On all 29 of these occasions, including three reports written by the BRE, the consultant missed the fact that the test was a failure. This meant Kingspan was able to use the failed test to bolster its case that its combustible product was suitable for high rises.
Finally, towards the end of the week Mr Clark's former boss, Stephen Howard (pictured), business group manager at the BRE, was asked why in 2015 he issued a classification report for a test Kingspan which had been carried out in 2005.
This test Kingspan had never been formally appraised against the pass fail criteria despite being widely cited by Kingspan as evidence that its product could be used on high rises.
The firm - by this point under pressure to prove its claims - belatedly sought the classification report in 2015. Mr Howard’s colleague, Tony Baker, cautioned against issuing it.
His worry was that the tested system - using a cement board - was unlike real-world cladding systems.
“I doubt this [the system tested in 2005] would be considered a complete system,” he wrote. “Data such as this has been misrepresented in the market in the past.”
But Mr Howard told a junior colleague to issue the classification report anyway. Grilled on why, he explained that he did not feel it was up to the BRE to make judgements about whether or not a system was realistic.
Finally, We also learned a little about Mr Clark’s career since the Grenfell Tower fire. He left the BRE in December 2017, having received “a very good offer to change” from rival test house Exova Warringtonfire.
But a year later, he left that job too - this time having been made “an even better offer” by Kingspan. His role at Kingspan was to set up the firm’s own in-house testing facility.
But in June 2020, he was very abruptly made redundant - a move he linked to the revelations which were soon to be made by the inquiry.
“It wasn’t long after that happened that the information came out of what Kingspan had been doing in terms of the falsification of tests. I think that may have played a little part,” he said.
He has since moved to certifier the British Board of Agrement where he is helping them “putting into practice lessons learnt as a result of the Grenfell Tower fire”.
The inquiry continues next week with further evidence from Mr Howard.
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. Peter 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
Grenfell Tower: a timeline of the refurbishment
Following the conclusion of module one of the Grenfell Inquiry’s second phase, Peter Apps presents a timeline of the key moments during the fatal refurbishment of the west London tower block
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
Week 21: ‘It’s there in black and white isn't it? We see a complete absence of any consideration of life safety’
The story of insulation giant Kingspan’s testing and marketing of its combustible insulation for high rises was unpacked in minute detail this week. Peter Apps reports
Week 22: ‘All we do is lie in here’
In the third week of evidence from insulation giant Kingspan, the inquiry continued to uncover shocking details about the firm’s behaviour both before and after the Grenfell Tower fire. Lucie Heath reports
Week 23: ‘That would have come as an earthquake to you at the time, would it not?’
This week the inquiry took its deepest dive yet into the inner workings of the cladding manufacturer whose product has been blamed for the terrible spread of fire up Grenfell Tower. Nathaniel Barker reports
Week 24: ‘Do you accept that Test 5B was Arconic's deadly secret’
The president of the firm that made and sold the cladding panels installed on Grenfell Tower was asked to account for the apparent concealment of “disastrous” fire tests on the product this week. Peter Apps reports
Week 25: ‘This is quite an incredible list of omissions and missed instances, isn’t it?’
This week the Grenfell Tower Inquiry heard its first witnesses from the Building Research Establishment (BRE) - the testing house which carried out key fire tests on the Kingspan and Celotex insulation products which were later used on Grenfell Tower. Peter Apps reports.
Week 26: 'You were taking an enormous risk, weren't you?'
Week 26 at the Grenfell Tower Inquiry was a key moment in understanding how dangerous products used on the tower came to be accepted by industry professionals. Dominic Brady reports
Week 27: ‘What will happen if one building made out [of] PE core is in fire and will kill 60 to 70 persons?’
The most explosive week at the Grenfell Tower Inquiry came not from those who did not attend, as the evidence which would have been presented to Arconic witnesses was displayed in their absence. Peter Apps reports
Week 28: ‘This is a serious safety matter’
This week the Grenfell Tower Inquiry zeroed in on the British Board of Agrément, the body that produced “misleading” certificates which inspired trust in both the cladding and insulation used on the tower. Lucie Heath reports
Week 29: ‘Is it true that Kingspan’s position… was to do its best to ensure that science was secretly perverted for financial gain?’
The final week in this section of the Grenfell Tower Inquiry primarily examined the attempts by insulation manufacturer Kingspan to lobby government after the fire. Peter Apps reports
How the products used in Grenfell Tower's cladding system were tested and sold
As the section of the Grenfell Tower Inquiry examining how the products used in the cladding system were tested, marketed and sold comes to a close, Peter Apps summarises what we have learned about each of the products included in the system.
Week 30: ‘There is certainly a high probability that in the event of a fire the whole building can become an inferno’
The focus of the inquiry shifted this week to the actions of the social housing providers responsible for maintaining Grenfell Tower. Pete Apps recaps what we learned.
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