Former architect David Gibson ‘saw no need’ for CDA but admits he did not understand cladding system proposed for tower
The organisation that managed Grenfell Tower and was the client for its fatally flawed refurbishment has insisted that the decision not to hire an independent design advisor to assist with the project was not taken to save money.
David Gibson, a former architect, told the Grenfell Tower Inquiry the fact that bringing in a client design advisor – or CDA – would have cost at least £30,000 was not the reason project consultant Artelia’s suggestion was rejected.
Gibson who was head of capital investment at the Kensington and Chelsea Tenant Management Organisation (KCTMO) from 2013-2016, said he had taken the view that the organisation did not need a CDA, even if one had been available for much less than the anticipated cost.
Giving evidence to the probe into the background to 2017’s fire, which claimed 72 lives, Gibson said he was confident in the abilities of project architect Studio E and expected the practice to be vocal if its designs were compromised by subsequent main contractor Rydon.
Gibson, who worked as an architectural assistant at Hackney council in the 1980s and then for a small private practice before moving into the social housing property services sector, said that appointing a CDA to provide extra design checks would have been “additional to contract requirements”.
“It’s not something I’ve ever previously been recommended to have,” Gibson said.
“I believe we had the suite of contractual documents that were required, we had the designers on board so I didn’t give it a great deal of consideration. Some of it, I thought, was doing a check that the clerks of works were already doing on site.”
Gibson told Wednesday’s hearing that at the time the idea of appointing an experienced architect to advise the TMO on value engineering and design compliance was mooted, all major design decisions on the project had been taken.
“I don’t think there was any stage where I felt the need to pick up the phone in terms of getting design advice. The design decisions that we were taking at that stage, post tender, were relatively minor,” he said.
Gibson said that as design and build main contractor Rydon, in conjunction with Studio E, was responsible for ensuring that the cladding put on the outside of Grenfell Tower was compliant with Building Regulations. He said he wouldn’t have expected the TMO to have had input on the design in relation to the overcladding.
“There was no contractual requirement for us signing off design, there was only a contractual requirement for the contractor to develop designs and construct,” he said.
However the new building envelope added to Grenfell Tower has already been established as absolutely failing to comply with Building Regulations. In the case of the aluminium composite material (ACM) cladding and insulation, it actively aided the spread of fire on 14 June 2017 according to the Grenfell Inquiry’s phase-one report.
Last week, Philip Booth – an Artelia staff member who was employer’s agent for the TMO for part of the Grenfell project – told the inquiry he believed saving money was part of the motivation for not employing a CDA to provide design challenge.
Gibson rejected the suggestion on Wednesday.
Inquiry chair Sir Martin Moore-Bick asked him whether KCTMO wouldn’t have accepted the services of a CDA even if they were free.
Gibson replied: “Free? Possibly. But I didn’t feel there was a need for the role and I wasn’t particularly interested in the role. It was an additional service that Artelia had told us some clients choose to have. There was no recommendation that we should have it.”
Studio E’s lack of experience
Gibson told Wednesday’s hearing that he was not aware that Grenfell Tower was Studio E’s first high-rise overcladding project.
But he said the practice was already project architect on the job when he joined KCTMO in 2013 and he had no reason to doubt the firm’s capabilities, not least the practice’s project lead for Grenfell, Bruce Sounes.
“The scheme was very well developed from when I had looked at their Stage C/D report. It looked very professional,” he said. “I met Bruce Sounes, he came over very well and very competent. I had no reason to think they didn’t have the ability to do this.”
Gibson said that even if he had known Studio E had never done a high-rise overcladding project before, he would “not necessarily” have been concerned.
“There’s a point in anyone’s career where they’re doing something for the first time. There shouldn’t be anything technically difficult about overcladding a building,” he said.
“Complexity comes in with high-rise and access and other areas. But cladding is something that’s very common in the industry.”
Gibson subsequently told the inquiry that when value engineering savings were sought on the cladding for Grenfell Tower, which eventually resulted in the switch from zinc to ACM cassettes, discussions had been focused on “cost not on performance”.
The inquiry heard that by 2013 the TMO was aware of a £2m gap between its £9.4m budget for the refurbishment and prospective contractor Leadbitter’s price for the work.
Gibson said that in looking for savings on the cladding the TMO had purely been focused on how alternative materials would look because it had been taken as read that all proposed alternatives would meet Building Regulations requirements.
“We were not expecting to be offered materials that were not compliant, so we weren’t asking questions about compliance,” he said.
“We knew there was a requirement for the materials that were used, and how they were put together, to be in accordance with regulations and legislation. So we weren’t having that type of discussion.”
He added: “My assumption, rightly or wrongly, was that there are many, many properties in London with aluminium cladding and this was aluminium cladding. I didn’t think any further than that.”
Not familiar with ACM system
Gibson told the inquiry that he had “assumed” the cladding to be fitted to Grenfell Tower would be single panels with insulation incorporated into them offsite until Rydon contracts manager Simon Lawrence informed him otherwise in 2015.
He said the knowledge had given him concerns that space between the insulation and the ACM panels could be a fire risk, based on the 2009 Lakanal House fire in Southwark. Gibson’s first witness statement to the inquiry said he had sought assurances about the safety of the cladding system from Lawrence, who told him all the materials being used were “completely inert”.
No minutes exist from the meeting and Lawrence denied giving such an assurance in his evidence to the inquiry in July.
Inquiry barrister Richard Millett QC asked Gibson whether it was “a pretty major misunderstanding” for the TMO, as a professional and educated client, not to have known that the cladding system for Grenfell Tower contained a range of different components.
“I accept that not having been involved in an over-cladding project before that I hadn’t considered it,” Gibson replied. “We’d never talked about the insulation, separately. We talked about the level of thermal efficiency we needed to achieve.”
Gibson said the “firm response” he claims to have received from Lawrence had given him reassurance that the fire safety issues he considered in relation to the cladding were not a problem.
“I thought, they’ve done this before, he knows the materials and I’ve just assumed something wrong about the insulation,” Gibson said.
“His response was immediate. I was confident he knew which materials he was fitting.”
The inquiry continues.