Over 150 schools in Britain are so structurally flawed they are on the point of collapse, endangering the lives of children and staff. The news was revealed just days before the autumn term starts on Monday.

The buildings in question contain reinforced autoclaved aerated concrete, known as RAAC. The lightweight, cheap material was used extensively across the UK and in many types of buildings, including hospitals, from the 1950s to the 1990s and has passed its 30-year design life.

RAAC is filled with air pockets, degrades in wet conditions, and lacks the strength and durability of ordinary concrete. In 1982, RAAC production in the UK ended amid safety concerns, and the Building Research Establishment subsequently declared it life-expiring after 30 years. The material is still used in China, central Asia, India and the Middle East.

The problems with RAAC have been known for years, with the first crack appearing in a UK building in 1995. A national audit was begun in 2018 after the roof of a primary school in Gravesend, Kent collapsed in 2018 above the school staff room, also damaging toilets, computers and furniture. It was only due to the collapse occurring on a Saturday that deaths and injuries were avoided. The roof only began showing signs of stress 24 hours before the incident. Another unnamed school saw its RAAC roof collapse in 2017.

In September last year, the Office of Government Property (OGP), responsible for public buildings, issued a “Safety Briefing Notice” warning “RAAC is now life-expired and liable to collapse”. That summer, emails leaked to the Observer sent by senior officials at the DfE to Downing Street during Boris Johnson’s premiership warned many school buildings posed a “risk to life”.

More urgent warnings were issued in March this year, with experts pointing to the extraordinary £11.4 billion backlog in school repair work—even higher than the National Health Service’s £10.2 billion.

Any remedial work is being carried out at a glacial pace. The response after 2018 consisted of the Department for Education (DfE) sending a questionnaire to schools asking if they had any confirmed or suspected cases of RAAC. Only if the school said yes did the DfE sent out engineers to confirm it. Of the 14,900 schools potentially having RAAC, just 6,300 informed the DfE they had completed work to identify whether RAAC had been used.

Schools Minister Nick Gibb revealed to the media Friday morning, three days before schools were due to open, that events over the summer involving a particular type of concrete had shown educational and other buildings to be unsafe. This included a beam collapsing on school premises, despite there being no external signs it was a “critical risk”—another life-threatening event.

The day before, when the story broke that a number of schools would have to close due to RAAC, Education Secretary Gillian Keegan said affected schools would contact parents directly, adding, “If you don’t hear, don’t worry”. Appearing Friday morning, Gibb could not provide any figures on the number of schools needing to be closed, saying, “We don’t know yet.”

The DfE has announced that 156 schools are at risk, with 104 requiring urgent action and only 56 identified earlier having received repair works.

Government officials have recklessly played down the dangers. Speaking to LBC’s Nick Ferrari radio programme, Gibb said some schools would have their ceilings propped up with steel girders. Asked if he would be happy for his young nieces and nephews to sit in a classroom under a ceiling propped up by a steel girder, Gibb replied, “Yes, because we’re taking a very precautionary approach. Some say we are being overcautious in dealing with this.”

It is not yet confirmed but according to the Press Association, 24 schools have been told to close entirely.

The problem is vast and requires a mass shutdown and repair of schools nationwide. The Guardian reported, “One schools estates manager told the Guardian that the number of those affected in some way could eventually rise as high as 1,000 and said the crisis could end up with children being taught in temporary buildings for as long as a decade to come.”

Gibb said more than he intended when interviewed by GB News. “By the way, RAAC applies only in the period [between] the 1950s and the 1990s, so schools built or extended before that period or afterwards—which is about half the school estate—will not even need to consider whether they have RAAC.” The other half is therefore at risk.

Figures obtained by the Scottish Liberal Democrats in May revealed the substance was present in at least 37 Scottish schools.

Due to the refusal to act by successive governments, the full extent of the problem beyond schools—in hospitals, public housing and other buildings—is unknown. Fully seven months ago the Mirror reported, “Over 30 NHS buildings and hospitals are ‘ticking time bombs’ that could ‘collapse without warning’ and it will cost more than £1 billion to repair them.” According to Mid Cheshire Hospitals Foundation Trust chief executive James Summer, seven of those identified were “made nearly exclusively” of RAAC.

The government has identified five hospitals constructed mostly from RAAC which will not be rebuilt until 2030 at the earliest. The north west of England has 11 hospital buildings built with RAAC, including seven with roofs made from it. According to a Manchester Evening News assessment last month, “Current government plans would not see removal of this concrete from all affected hospitals [in the North West] for another 13 years.”

The government, which has imposed £10 billion in school budget cuts since 2010, at first insisted as late as Thursday evening, “We expect you [schools] to be able to fund anything that is an additional revenue cost, for example rental costs for emergency or temporary accommodation for education settings or additional transport costs for local authorities.’

By Friday morning, forced into damage limitation mode, Gibb had to say Whitehall would cover “all capital costs” over any disruption. He made clear the type of alternative accommodation being considered: “So if, in the worst-case scenario, we need Portacabins in the school estate… we will cover all those costs.”

The idea that schools will be quickly able to find suitable space for thousands of pupils, and transport to the new locations, in a country which can barely run functioning school and transit systems at the best of times, is ludicrous. Such an unserious response is indicative of the ruling class’s total disregard for the vast majority of children’s education. Its sole imperative, at it was during the height of the pandemic, is to keep them in schools so that parents can go to work, whatever the risk—whether of infection with Covid or a classroom roof coming down on their heads.

Schools still have next to no mitigations in place against the spread of COVID-19, with a renewed surge underway globally. As far back as April 2022, the government ended routine testing for the virus in educations and children’s social care settings.

This is accepted by and the responsibility of the trade unions, which have not lifted a finger to defend the safety of their members, working in COVID and asbestos ridden, structurally unsound schools for years.

The National Education Union, the largest teaching union, issued a statement Friday proposing no action, only reiterating, “The NEU and sister unions have been raising concerns ever since [2010] and pressuring education secretary Gillian Keegan in recent months to release a list of RAAC-affected schools”. Their sole demand was that the “Government must fund all costs for schools affected by RAAC.”

Educators cannot accept this criminally complacent approach to their safety and that of the children in their care. Those working in unsafe schools must take the initiative and refuse to teach under such circumstances. Walkouts must be united in strikes to demand the necessary billions be secured from the super-rich to fund an emergency mass renovation programme and the remote learning and working alternatives required.