![Singlewell primary school in Gravesend where roof collapsed in 2018](https://www.telegraph.co.uk/content/dam/news/2023/08/31/TELEMMGLPICT000347452730_16935137208150_trans_NvBQzQNjv4BqY4-XNG_7v-V2jIZ3ghNYKOB8VXEHCs73yexWqFsf2H4.jpeg?imwidth=680)
Crumbling school roofs prompted drastic action to safeguard children
Years of inaction over dilapidated sites finally takes its toll, as structures cave in 'without warning'
![Singlewell primary school in Gravesend where roof collapsed in 2018](https://www.telegraph.co.uk/content/dam/news/2023/08/31/TELEMMGLPICT000347452730_16935137208150_trans_NvBQzQNjv4BqY4-XNG_7v-V2jIZ3ghNYKOB8VXEHCs73yexWqFsf2H4.jpeg?imwidth=680)
It was the discovery of rubble in classrooms at a school thought to be safe that prompted the Government to take drastic action and halt the return from the summer holidays for thousands of children.
After years of inaction, the Department for Education went into panic mode when it found that planks of lightweight, bubble-like concrete previously considered a “non-critical” risk had caved in at one school “without warning”.
No pupils were inside but the collapse prompted the order for more than 100 schools to close their doors or shut crumbling classrooms over the risk posed by Reinforced Autoclaved Aerated Concrete (RAAC).
More closures are expected as an estimated 700,000 children are taught in dilapidated schools. Experts are already predicting a billion-pound headache for the Government.
Weak and likened to Aero chocolate bars
Described as weak and likened to Aero chocolate bars, RAAC, reinforced with steel rods, was almost ubiquitous in public buildings built in the 1960s and 1970s and was used for roofs and occasionally walls and floors up to the 1990s.
The material is vulnerable to moisture, which can cause corrosion and when it does collapse, deterioration can be rapid.
Successive governments going all the way back to John Major in the 1990s have been warned of the risks of RAAC, which is meant to have a lifespan of 30 years but has long outlived its expectancy in many public buildings.
However, there was little action until five years ago, when the flat roof collapsed at Singlewell Primary in Gravesend, Kent.
Just 24 hours after signs of structural stress were spotted, the roof came crashing down over the staff room, computer learning area, and school office.
Fortunately, the accident occurred at a weekend, but the move prompted Kent County Council to warn other authorities about the danger.
A year later, the Standing Committee on Structural Safety recommended all planks installed before 1980 be removed. Last year, the Office for Government Property warned the material was “now life expired and liable to collapse”.
The Government started a survey in March 2022, to monitor the crumbling concrete but is now taking more urgent action where pupils are known to be taught in classrooms beneath the material. It may be some time before officials can estimate the scale of the problem, with responses from many schools still outstanding.
The plea by Gillian Keegan, the Education Secretary, for parents not to worry is likely to be of little comfort to those fearing their children now face the biggest disruption to their education since the Covid lockdown.
Around 24 schools will have to fully close their doors and find alternative teaching spaces, it is understood. In total, more than 100 schools have been told to find emergency accommodation until classrooms are made safe.
On Thursday, some schools were already telling parents that their children would be moving to online learning for the first time since the pandemic.
Ferryhill School in Co Durham was built in 1964 but has been used for more than twice the recommended lifespan of RAAC.
On Thursday, it told parents it would only be able to welcome Year Seven students, and other pupils would be taught by “live remote education” from the start of term after it discovered problems in its “two main blocks”.
Pupils at other schools, some rated outstanding by Ofsted, will return from the summer to portable cabins rather than school corridors as teachers desperately try to source temporary classrooms.
Among those with temporary classrooms are Springfield Primary in Essex, which has been trying to make the school safe throughout August.
At Mistley Norman CE Primary, children have been moved to another school within the trust as government officials consider a complete rebuild.
Industry experts have long warned of the safety risks of buildings with RAAC concrete. The Royal Institute of British Architects (Riba) has accused the Government of not “putting enough money in the pot to address the scale of the problem”.
Simon Allford, president of Riba, said: “It is a huge concern that 700,000 pupils are being taught in buildings that require major rebuilding or refurbishment - it is a clear failure of the Government.”
Warnings over the material go back to 1996 when the Building Research Establishment reported that there were clear structural issues with RAAC, advising the Government to inspect buildings with this material.
The construction industry also points out its use in ‘legacy buildings’ which can extend to several post-war structures including NHS hospitals.
One of the worst affected is West Suffolk Hospital in Bury St Edmunds, where staff were forced to install 27 metal supports under RAAC planks to make it safe.
Management became so concerned they asked a law firm to produce a report into the risk of “corporate manslaughter” charges should a fatal roof collapse happen.
‘Perfect storm’
Matthew Jones, UK head of construction and engineering at law firm Taylor Wessing, said buildings should have regular or annual inspections and people should be banned from entering if the risk is too great.
“Any remedial action should be proportionate, so if there were serious health and risks, that should be urgently dealt with – and that may also require prohibition on occupation and use if appropriate until repairs are satisfactorily completed,” he said.
Many estate managers do not know if their roofs or walls are made of the material due to incomplete documentation from decades ago and in an echo of the cladding crisis following the Grenfell Tower disaster, the cost to address this is likely to be huge.
Prof Chris Goodier, professor in construction engineering and materials at Loughborough University, said there are a few options when it comes to replacing RAAC roofs, and predicted a bill of up to £1 million per school.
Additional strengthening of existing RAAC, which is still used internationally but not in the UK, can be done to make it safe and sound and this has been the preferred method for afflicted NHS hospitals, he said.
“It depends on the scale but it would cost a school hundreds of thousands of pounds to replace the RAAC roof. It might reach £1 million for a secondary,” he said.
Prof Goodier added that said RAAC can last for decades if looked after properly but was often not waterproofed or overloaded and poor quality control in the Sixties and Seventies was an aggravating factor.
“If you have a perfect storm of it not being built properly, not being looked after and you’ve overloaded it, then you’ve got a problem,” he said.