DfE urges schools built using Reinforced Autoclave Aerated Concrete to close affected buildings

The government is advising more than 100 schools to close high risk buildings before the start of the new term as it updates its guidance on structures built with a "weaker" form of concrete and follows on from concerns about the use of the material in hospitals.

A sudden roof collapse at a primary school in Essex in 2018 brought the RAAC issue to light and now a total of 20 hospitals at 18 NHS trusts around the UK have been identified as suffering from the blight. It has seen the NHS implement emergency supports and monitoring systems on seven badly affected hospitals around the country that have been built with RAAC.

NCE's coverage of RAAC in recent years includes claims in 2021 that the issue with RAAC could be as problematic as that found with use of High Alumina Cement in the 1970s. In July last year NCE reported that Mott MacDonald was undertaking a review of the RAAC risk to hospitals and in February this year it was reported that Edinburgh Council was examining 15 buildings over RAAC concerns.

A series of FoIs sent out by NCE revealed that the hospitals worst affected by RAAC will need hundreds of millions of pounds for remedial works.

The decision today regarding schools follows on from an inquiry into the use of Reinforced Autoclave Aerated Concrete (RAAC) in schools began in March last year. Now the Department for Education (DfE) has announced it is advising schools with confirmed or suspected RAAC in its buildings to close fully or close off affected spaces.

While the total number of schools that have buildings built with RAAC is currently not known, the DfE has contacted 104 schools where RAAC is confirmed to be present, urging them to vacate spaces or buildings that are known to contain RAAC.

RAAC is a building material made from a combination of cement, lime, water and an aeration agent. It speeds up the manufacturing turnaround of precast concrete units and was used in schools and hospitals between the 1960s and 1990s. However, there is a high volume of air within RAAC, making it vulnerable to moisture ingress and it is now known to lose tensile strength in situ. As these buildings are now passing their 30 year lifespans, recent years have seen structural failures occurring at increasing frequencies.

A statement from the DfE said: “The guidance advises responsible bodies to vacate and restrict access to the spaces with confirmed RAAC. Spaces should remain out of use until appropriate mitigations are in place, even where they would have been deemed non-critical previously.”

While the department has been working to manage the potential risks of RAAC since 2018, new cases have made it less confident that buildings containing RAAC should remain open without extra safety measures in place.

In June, the government expanded its inquiry into the use of RAAC to include the whole public estate rather than just schools as it was initially planned.

Four schools were shut earlier this year after RAAC was discovered in their buildings.

The DfE’s current guidance states that schools “should vacate and restrict access to the spaces with RAAC and ensure that they are out of use. If the RAAC is in a small enough area, you may be able to do this with minimal disruption to the operation of the school, college or nursery school.

“You may already have a contingency plan in place, which you can activate at this point. We know that for larger settings with higher numbers of pupils you may need additional support to develop and implement arrangements to ensure continuity of provision.”

Where RAAC is found, the DfE will write to the school and assign them a caseworker from the department’s capital team to discuss remediation measures. The DfE will provide funding for all mitigation works that are capital funded.

It has not stated how long it expects the remediation works to take.

The DfE said: “We have been proactively monitoring all confirmed cases of RAAC closely. Recent cases have led to a loss of confidence in buildings containing the material, leading us to advise education settings (schools, colleges and maintained nursery schools) to vacate all spaces or buildings that are known to contain RAAC, unless they already have mitigations in place to make the building safe.

“We’re working hard to make sure any disruption to education is kept to a minimum.

“The vast majority of schools will be unaffected. Your child should attend school as normal in September, unless you hear differently.”


Like what you've read? To receive New Civil Engineer's daily and weekly newsletters click here.

Related articles

Have your say

or a new account to join the discussion.