THE INSULATION used in the refurbishment of Grenfell Tower was ‘originally suggested’ to meet an ‘aspirational’ thermal efficiency target, but without any ‘basic checks’ regarding fire performance.

The inquiry resumed on 7 September, and its first day saw Rydon’s commercial manager state that the company ‘struggled’ to find cladding specialists for the refurbishment of the tower. Last week, Harley’s owner Ray Bailey said that he did not know that Celotex insulation was flammable, and accused the company of ‘misleading’ his firm.

It was then revealed that his 25 year old son – Ben Bailey - was hired to project manage the refurbishment, while he had also called for a full combustibles ban; other Harley staff continued to testify, with no technical manager said to have been in place that was qualified to advise on fire performance, and an estimating error was made about cladding costs.

Then, its former design manager revealed that emails, documents and drawings relating to the refurbishment ‘appear to have been lost forever’ after a laptop was wiped. Recently, it was revealed that ‘nobody’ at Harley ‘was designated with the responsibility of assessing the fire safety of products used’, alongside a series of revelations about lack of experience, cost issues and competence.

More recently, Ben Bailey revealed that the insulation used was sold ‘at almost 50% discount’ for use on the tower.  evidence from Mr Bailey and cladding fabricator CEP’s senior sales manager Geof Blades. Earlier this week, Harley’s project manager admitted that he had not understood a warning about cavity barriers; one of the fabricators denied recommending the aluminium composite material (ACM) used; and other issues were raised.

Inside Housing has now reported that the insulation used on the tower was suggested to meet an ‘aspirational’ thermal efficiency target, but no ‘basic checks’ on fire performance were made. Andrew McQuatt, project engineer for the refurbishment at consultancy Max Fordham, stated that a target appropriate for new buildings had been set for Grenfell’s insulation, ‘double the standard set in guidance for refurbishments’.

An email Mr McQuatt sent in August 2012 to lead architect Bruce Sounes saw him state that the Celotex FR5000 ‘is the only type of product that will give us the required performance’, but the material is not only combustible but also releases a combination of toxic gases when burnt, including cyanide, and does not meet the standard of limited combustibility that is required for buildings 18m or taller.

Inquiry counsel Kate Grange asked Mr McQuatt if he had ‘fire performance in mind’ when making the suggestion, to which he said ‘I had the Lamba values [insulation performance] in mind. There was nothing that sparked any concern that it wasn’t okay’. She asked in turn if he made ‘any consideration of its fire performance in any way at all’, to which he replied ‘no’; and he was then asked why he didn’t carry out ‘even basic checks to its fire performance’ before suggesting it.

In response, Mr McQuatt said he believed that as plastic insulation was already being considered, he ‘did not believe this would be different’, adding that ‘I wasn’t aware that I was suggesting anything new into the project. I thought it was already there and established in the use of Kingspan’. He also explained that he did not believe the ‘high target’ for insulation would be an issue, as the work being carried out ‘was similar to a new build’.

He stated: ‘If you were to build a new concrete building, you would apply insulation and apply rainscreen [cladding panels]… it was very similar to how you would construct a new build so it didn’t seem crazy or difficult to achieve.’

The target was described in emails and documents as ‘a bit aspirational’ and ‘over the top’ however, with planning documents showing that he had called insulation the ‘top priority’ for the project, and that he intended to ‘far exceed’ requirements of building regulations. Despite this, non combustible Rockwool insulation was discounted after the team ‘decided that to meet the standard, it would become too thick for the cladding system they were planning’.

Mr McQuatt was then shown calculations by inquiry expert Paul Hyett, which ‘disputed’ this assertion and proved Rockwool material could ‘have come close to the required level within the specified thickness’. He responded that he did not disagree with the conclusions, and with the calculations taking impact of thermal brackets into account, they may have been ‘more accurate’.

Thinner alternatives from plastic insulation manufacturers were researched by Mr McQuatt after he discounted Rockwool, and he found Celotex FR5000 ‘having been unable to log into rival manufacturer Kingspan’s website’, adding that if he had been able to log in ‘he would likely have suggested Kingspan’.

Mr Sounes’ testimony was shown, in which he said he took this recommendation as ‘evidence’ that the product was suitable for high rises, and Mr McQuatt said this was an ‘inference’ he had not realised would be made. Asked if he was aware that the Celotex insulation was combustible, he said: ‘It sounds so silly to say this now, but it just never occurred to me in any way that something I could just go on to the website and buy could be so unsafe.’

In turn, he noted that he had seen Celotex used on jobs ‘again and again and again’, but acc epted he had not previously worked on a high rise, while the company passed a large scale test in 2014 clearing the product for use on high rises ‘in a specific combination using cement-fibre cladding’. It had not passed this when Mr McQuatt suggested it for Grenfell however.

Extra evidence was given by Jon White, the clerk of works for John Rowan Partners, which had inspected the building work. Mr White made ‘at least 10’ trips up the building to inspect cladding, adding that ‘we would go top to bottom to the third floor and then go across to the next climber and then all the way to the top of the building and down again. I would be recording with my iPad all the snags and then I would issue that report to Rydon who would issue it to the cladding contractor’.

Mr White said he did not know what materials were being used, and that his role was a ‘site inspector’ and not a full clerk of works, claiming that the role meant he was not required to check them. He was then shown a description of the role for the project, which ‘specifically’ said he should be ‘familiar with legal requirements and checking that the work complies with them’.

He said he did this by checking that building control inspectors at the Royal Borough of Kensington and Chelsea had signed the work off, but ‘accepted’ that he made no individual assessment. He was also shown images of horizontal cavity barriers installed vertically and back to front, and said he ‘had not seen work of that kind’ during his inspections. His impression of the cladding work was that it ‘looked very neat’, and that that was a ‘good way of knowing it’s being done properly’.

Mr White commented: ‘It doesn’t look right and [if I had seen it] I would have taken a photo and put it in my report. [But] I was only there one day a week and I didn’t go up… every time. When I started in this industry, all the responsibilities were clear. The architects was the lead designer… and you had a builder to build. Now it’s all mixed up… I wish we could go back to the way it was when I started.’