The UK’s two busiest airports, Heathrow and Gatwick, have found the crumbling concrete that has already forced hundreds of schools and dozens of hospitals to close.
At the same time, dozens of UK hospitals are preparing to evacuate staff and patients if buildings show any concerning signs ahead of an extensive review of the NHS.
As reported last week, the risk of injury or death from a building collapse caused by deteriorating reinforced autoclaved aerated concrete was “very likely and critical,” according to the UK National Audit Office (NAO).
The UK Government is now racing against time to replace crumbling RAAC with timber joints in what has become an existential threat to Rishi Sunak’s leadership.
However, experts are quick to note that the integrity of buildings that contain the faulty material is of most concern in structures that have been poorly maintained, which lack building logs and where structural upgrades and repairs have been inconsistent.
These include schools, hospitals, shopping centres and even theatres.
On Wednesday, the House of Parliament was assessed for potential collapse. A House of Commons spokesperson said: “Routine ongoing in-house investigations are currently taking place as to whether any parts of the parliamentary estate have Raac.”
The concrete was found at Heathrow’s Terminal Three last year, with the airport now “acting on the remedial steps” and working on a “permanent solution” for the terminal.
The furore over schools led Heathrow to assess its management of the material. It has since concluded that its original plan remains suitable.
Chris Goodier, professor of construction engineering and materials at Loughborough University and one of the UK’s foremost experts, said the material’s presence poses much less of a threat at airports than at schools and hospitals.
“There are people there running the place seven days a week with a big full-time maintenance team whose only job is to keep it running 24/7,” he said.
Professor Goodier tabled a report to the National Health Service in 2021, which outlined the elevated risk of structural collapse due to deteriorating RAAC. He now calls for far greater monitoring and surveillance across tens of thousands of buildings where the material has been used extensively.
Responding to the threat caused by RAAC, Gatewick Airport has an RAAC register, “which is closely monitored through a regular comprehensive structural inspection regime.”
Its most recent inspection was in June 2023, “and it did not present any concerns,” a spokesperson added.
Along with schools, hospitals are the most significant concern
Meanwhile, the NHS has ordered an urgent review of dozens of hospitals built using the material.
Seven hospitals in England have been identified as ‘high-risk’ thanks to RAAC exposure, two of which already have been replaced, with plans for the other five soon to be underway in the Government’s new hospitals program.
Under the plan, the Government is looking to fully replace hospitals “made nearly exclusively” from RAAC by 2030. However, that timeframe could now be accelerated, given the elevated risk of collapse.
List of NHS hospitals “made nearly exclusively” of Raac:
- Queen Elizabeth Hospital, King’s Lynn
- Leighton Hospital
- James Paget Hospital
- Frimley Park Hospital
- Hinchingbrooke Hospital
- Airedale Hospital
- West Suffolk Hospital
Other NHS hospitals and buildings affected:
- Broomfield Hospital, Building 60
- Blackpool Victoria Hospital, Block 44 and Block 8
- Southampton General Hospital Laboratory and Pathology Block
- Bassetlaw and District General Hospital mental illness buildings and theatres 1-4
- Kidderminster Hospital Block A
- Scarborough General Hospital pathology, pathology link corridor, theatre, attic, plant room, and north/south block link corridor.
- Royal Blackburn Teaching Hospital Level 4, R14 and R15
- The Royal Oldham Hospital roof and The Salford Royal Turnberg building
- Haywood Hospital
- Aintree University Hospital Tower block plant rooms, main kitchen, Clinics A, B, C, D, and F, Domestic services centre, imagine department, Ward 6, theatre A plant room/recovery, pre-op.
- Haverhill Health Centre
- Warren Farm Health Centre
How can buildings with crumbling RAAC be fixed?
According to advice published in April by the UK Institution of Structural Engineers, at least five options are available when tackling Raac.
These remediation strategies include:
- Adding secondary supports or beams at the end bearing to increase the bearing length.
- Adding positive remedial supports to take the loading from the panels actively. This could include new timber or lightweight structures to support the panels directly.
- Passive fail-safe supports mitigate the panels’ catastrophic failure if a panel fails. This could be a secondary structure designed to support the panels.
- Removal of individual panels and replacement with an alternative lightweight solution.
- Entire roof replacement.
Primarily used in architectural layouts in schools, hospitals and other buildings, its panels can span up to six metres without an intermediate support column, are lighter than standard concrete and can be easy to build and dismantle.
Globally, the product has been used widely for decades – it is popular in Turkey and Japan, mainly due to its excellent earthquake performance and is still in production in Germany and the US.
- Wood Central will continue to provide updates about the crisis as more information comes. to hand
