The Grenfell Tower disaster was the result of “decades of failure” by central government to stop the spread of combustible cladding combined with the “systematic dishonesty” of multimillion-dollar companies whose products spread the fire that killed 72 people, a seven-year public inquiry has found. In a 1,700-page report that apportions blame for the 2017 tragedy widely, Sir Martin Moore-Bick, the chair of the inquiry, found that three firms – Arconic, Kingspan and Celotex – “engaged in deliberate and sustained strategies to … mislead the market”. He also found the architects Studio E, the builders Rydon and Harley Facades and the Royal Borough of Kensington and Chelsea’s building control department all bore responsibility for the blaze. Studio E demonstrated “a cavalier attitude to the regulations affecting fire safety”. Its failure to recognise that the plastic-filled panels on the high-rise tower were dangerous was not the action of a “reasonably competent architect” and it “bears a very significant degree of responsibility for the disaster”, the inquiry found. The inquiry was highly critical of the tenant management organisation (TMO), which was appointed by the local authority, the Royal Borough of Kensington and Chelsea (RBKC), to look after its thousands of homes but, according to the report, consistently ignored residents’ views. The TMO chief executive, Robert Black, established a “pattern of concealment … in relation to fire safety matters” and the TMO “treated the demands of managing fire safety as an inconvenience” in “a betrayal of its statutory obligations to its tenants”, the report said. The final report of the Grenfell Tower public inquiry comes seven years, two months and 21 days after the fire, which started behind a fridge in a fourth-floor flat. It raged through the combustible cladding system to the 24th floor in about 30 minutes. Some victims fell from windows, but most perished trapped by smoke and flames on the upper floors. Fifteen of the deceased were disabled. After 400 days of evidence in an inquiry that has cost the UK taxpayer more than £200m, Moore-Bick reserved some of his most damning conclusions for central government. It regulates the safety of buildings but failed to tighten up ambiguous fire regulations while it was engaged in a “bonfire of red tape” launched by the Conservative prime minister David Cameron from 2010 to 2016 in an attempt to boost the economy after the global financial crisis. The inquiry found that the government was “well aware” of the risks posed by highly flammable cladding “but failed to act on what it knew”. Eric Pickles, Cameron’s housing secretary until 2015, had “enthusiastically supported” the prime minister’s drive to slash regulations and it dominated his department’s thinking to the extent that matters affecting fire safety and risk to life “were ignored, delayed or disregarded”, the inquiry concluded. Pickles also failed to act on a coroner’s 2013 recommendation to tighten up fire safety regulations after a cladding fire at Lakanal House, another London council block, killed six people. It was “not treated with any sense of urgency”, the inquiry found and the tightening up had not happened by the time Grenfell went up in flames on 14 June 2017. In cross-examination under oath, Pickles vehemently insisted the anti-red tape drive had not covered building regulations. But the inquiry said this evidence was “flatly contradicted by that of his officials and by the contemporaneous documents”. Detectives from the Metropolitan police’s criminal investigation said they would spend 12 to 18 months poring over the findings “line by line” before possible charges. These could include corporate manslaughter, gross negligence manslaughter, fraud, perverting the course of justice and misconduct in public office. The Crown Prosecution Service is yet to make any charging decisions and any trials are not expected to start until 2027. There was criticism of of RBKC leaders and the inquiry concluded financial considerations drove a decision by Laura Johnson, the director of housing, to slow down installation of self-closing mechanisms on fire doors despite warnings from the London fire brigade that their absence compromised fire escape routes. She also opposed a new inspection regime. She did so “without having taken any advice about the consequences for the safety of residents”. Smoke spread into escape routes on the night of the fire through open doors with missing or defective closers. In the immediate aftermath of the disaster RBKC’s response demonstrated a “marked lack of respect for human decency and dignity” and its chief executive, Nicholas Holgate, was “unduly concerned” for the council’s reputation and “was not capable of taking effective control”. The report described the “long-lasting trauma” of “a community whose lives have been changed forever”. Survivors were “left to fend for themselves” in a scene some compared to a “war zone”, but “those who emerge from the events with the greatest credit, and whose contributions only emphasised the inadequacies of the official response, are the members of the local community”. The inquiry panel of Moore-Bick, the architect Thouria Istephan and the housing expert Ali Akbor also made recommendations for reform, including a new construction regulator reporting to a cabinet minister and an urgent review of building regulation guidance on fire safety. They suggested town halls could be stripped of building control functions, with a national authority created instead. The inquiry found that Rydon, the main contractor, displayed a “casual attitude to fire safety” and “bears considerable responsibility for the fire”, while Harley Facades, which installed the lethal cladding system, “bears a significant degree of responsibility for the fire” because it assumed others would check it was safe. Arconic, the US aluminium giant that supplied the plastic-filled cladding panels that were the main cause of the fire’s spread, “deliberately concealed from the market the true extent of the danger of Reynobond 55 PE in cassette form [the panels used on Grenfell], particularly on high-rise buildings”, the inquiry found. Celotex, which made most of the combustible foam insulation “embarked on a dishonest scheme to mislead its customers and the wider market”. And Kingspan, which made a small amount of the insulation, “knowingly created a false market in insulation for use on buildings over 18 metres in height” by claiming that a test showed it could be used in any building over 18 metres when this “‘was a false claim, as it well knew”. Moore-Bick concluded: “One very significant reason why Grenfell Tower came to be clad in combustible materials was systematic dishonesty on the part of those who made and sold the rainscreen cladding panels and insulation products. They engaged in deliberate and sustained strategies to manipulate the testing processes, misrepresent test data and mislead the market.” They were unable to do that in a vacuum, and Moore-Bick found that two private bodies that provide safety certificates for construction products that are used by designers and builders, Local Authority Building Control (LABC) and the British Board of Agrément (BBA), “failed to ensure that the statements in their product certificates were accurate and based on test evidence”. “The dishonest strategies of Arconic and Kingspan succeeded in a large measure due to the incompetence of the BBA,” he said. The LABC “was willing to accommodate the customer at the expense of those who relied on certificates. As a result the LABC was also the victim of dishonest behaviour on the part of unscrupulous manufacturers.” Responding to the inquiry findings, Arconic insisted it had been legal to sell the panels in the UK, rejected any claim its subsidiary sold an unsafe product and said it made test reports by third-party testing bodies publicly available and to customers. It said: “Arconic Architectural Products did not conceal information from or mislead any certification body, customer, or the public.” Kingspan said the report showed the type of insulation was “immaterial, and that the principal reason for the fire spread was the PE ACM cladding, which was not made by Kingspan”. It said it has “acknowledged the wholly unacceptable historical failings” in part of its UK business but these were “in no way reflective of how we conduct ourselves as a group, then or now”. “While deeply regrettable, they were not found to be causative of the tragedy,” it said. Moore-Bick said the Kensington and Chelsea Tenant Management Organisation – the 24-storey council block’s landlord, which wrapped the building in combustible cladding and insulation – had “lost sight of the fact that the residents were people who depended on it for a safe and decent home and the privacy and dignity that a home should provide”. In the years before the disaster, the landlord, which managed thousands of council homes for RBKC, allowed its relationship with the Grenfell residents to deteriorate to such an extent into “distrust, dislike, personal antagonism and anger” that it amounted to “a serious failure … to observe its basic responsibilities”. Some in the tower saw the landlord as “an uncaring and bullying overlord that belittled and marginalised them”, Moore-Bick said, while the housing officials “regarded some of the residents as militant troublemakers … The result was a toxic atmosphere fuelled by mistrust on both sides.” The landlord’s failure to gather information on disabled and vulnerable people that might assist with their evacuation in the event of a fire “amounted to a basic neglect of its obligations in relation to fire safety”. In the immediate aftermath of the fire, the council’s emergency response was “muddled, slow, indecisive and piecemeal” with aspects demonstrating “a marked lack of respect for human decency and dignity”. It was said to have “left many of those immediately affected feeling abandoned by authority and utterly helpless”. Many Muslim residents were observing Ramadan but RBKC had “no regard for their cultural or religious needs” and people suffered “a significant degree of discrimination in ways that could and would have been prevented if the guidance had been properly followed”, the report found.