A manufacturer of Grenfell Tower’s combustible insulation rigged tests and hired lobbyists after the disaster to try to persuade MPs that rival non-combustible products might be no less dangerous, the public inquiry has heard. The evidence came as the hearings were adjourned until January because a member of the inquiry team had tested positive for Covid-19. Weeks after the fire, on 14 June 2017, in north Kensington, London, Kingspan, an Ireland-based construction materials firm, recruited Portland, a Westminster public affairs consultant, to get its “manifesto in front of … decision makers” including MPs and Sajid Javid, then housing secretary, and Amber Rudd, home secretary at the time. The company feared a ban on combustible insulation and drew up a list of political targets, including Clive Betts, chair of the housing select committee, and Dame Judith Hackitt, appointed by ministers to propose building regulation reform in the wake of the fire, which killed 72 people. It also hired Grayling, another agency, to try to persuade politicians that combustible materials were “no more dangerous than non-combustible materials when properly installed”, according to emails shown to the inquiry. Needing evidence, in the spring of 2018 Kingspan set up tests to try to show that non-combustible rival insulation would also fail. It rigged them with deliberately “weak structural specification” and an assembly designed “to perform poorly”, according to internal emails. Some of the firm’s most senior leaders were involved. Gene Murtagh, Kingspan’s chief executive, and Gilbert McCarthy, its executive director, were copied in on planning emails about how to “generate evidence for use in both the political arena and with the Hackitt review team”. No one had suggested that non-combustible insulation such as the mineral fibre made by rival Rockwool was a fire risk, but Kingspan set out to suggest it could be in certain systems, the inquiry heard. The testing plan was to set fire to two walls using aluminium composite panels, with Rockwool insulation behind one and Kingspan’s plastic foam behind the other. Planning emails showed discussions about the need to create gaps to get “some ‘draw’ to get the flames to get above the … rig”, and about which panels “would give most fuel to get the flames up there”. Richard Millett QC put it to Adrian Pargeter, director of technical and marketing at Kingspan, that “Kingspan was engaged in a wholesale attempt to mislead Clive Betts and the select committee … because of the threat of a ban on combustibles, based on a deliberately manipulated test”. Pargeter disagreed. Millett continued: “The reality is that Kingspan’s position, even in 2018 in the face of a government investigation into fire safety after Grenfell, is doing its best to ensure that the science was secretly perverted for financial gain, and that has been your own approach and Kingspan’s general approach for years and it’s still going on.” “No, I disagree,” said Pargeter, who added that the tests were done to explore potential scenarios. The inquiry has already heard that the firm relied on an out-of-date test to argue that its material was safe for use on buildings more than 18 metres tall – guidance that was withdrawn only in October 2020 – and that employees said internally that they were being asked to “lie”. Kingspan has admitted to “process shortcomings during the period of 2005 to 2014 for which it sincerely apologises” but said it did not know its material was being used in the Grenfell Tower. Kingspan sent a summary of the results of three tests to Bett’s select committee investigating fire safety without disclosing that they had been designed to fail. Millett put it to Pargeter: “Materials of limited combustibility or non-combustible materials hadn’t actually caused any problem at Grenfell Tower, so what was the point in attacking their use?” Pargeter said the tests were to check “if that assumption was flawed”. The inquiry chair, Sir Martin Moore-Bick, asked: “Are we to understand that the reason for all of this testing was to benefit the public at large?” Pargeter replied: “I wouldn’t say it was entirely altruistic but it’s part of it.” At the end of the day’s hearing Moore-Bick said the decision to adjourn until 11 January was “extremely disappointing” but unavoidable. The inquiry has been running with only witnesses and key lawyers in attendance, with everyone else following via YouTube.