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Explains how RAAC has been used in Wales and the work being done to manage buildings with RAAC.

First published:
8 September 2023
Last updated:

What is RAAC

RAAC is a lightweight form of precast concrete, frequently used in public sector buildings in the UK from the mid-1960s to the 1990s, before devolution. It was invented in Sweden in the 1930s.

It is mainly found in roofs, occasionally in floors and walls. Visually, RAAC planks may look the same as pre-cast concrete, and may be hidden above false ceilings.

It is less durable than traditional concrete and there have been problems as a result, which could have significant safety consequences.

Research has shown that this material has a far lower structural loading capacity than other generic reinforced concrete products. Its condition deteriorates further if water is present, due to leaks from roofs etc, which can compromise the reinforcement bars contained within RAAC planks.

The lifespan of such planks has been estimated to be around 30 years.

How we’ve been monitoring and managing buildings with RAAC

UK governments have been aware of some of the vulnerabilities of RAAC since the 1990s. A safety alert was published in May 2019 by the Standing Committee on Structural Safety (SCOSS) following the sudden failure of a flat roof in a school made from RAAC.

The Welsh Government has been working with the UK Government and other devolved governments since 2018 to manage buildings with RAAC.

NHS organisations in Wales were notified about the risk of RAAC planks failing by the NHS Wales Shared Services Partnership (NWSSP) in November 2019. They were required to review all their buildings to see if any contained RAAC. Once the reviews were completed, a specialist structural engineer was appointed in November 2022, to review the reports and the locations where RAAC had been identified.

In February 2023, a further notice was issued to the NHS, on the recommendation of the specialist structural engineer to provide further assurances to NWSSP and the Welsh Government. The responses to this notice are being assessed.

Local authorities were made aware of the potential issue with RAAC through the Welsh Local Government Association (WLGA) in February 2020 after the safety alert was published by SCOSS in 2019.

Details of any instance or awareness of RAAC in schools is requested as part of the annual education data collection exercise and, since March 2023, the Welsh Government has been working closely with local authorities and the WLGA. A number of local authorities have completed their school estate review and it is underway in others.

In May 2023, the Welsh Government commissioned a condition and energy survey of all state-funded schools and colleges. This would highlight any structures suspected of containing RAAC for further inspection by specialist structural engineers.

On 31 August 2023, the UK Government said new information had emerged about RAAC in education settings. UK Government Ministers said a number of incidents happened over the summer period which meant there was a higher safety risk.

In response, the Welsh Government has commissioned urgent new surveys of public sector buildings, including schools. The NHS is finalising the survey work across its estate.

Are buildings with RAAC safe?

Having a regular inspection regime in place and ensuring buildings are properly maintained, will help to identify any issues with RAAC at an early stage.

Dr Wei Tan, Senior Lecturer at Mechanical Engineering, Head of Mechanics of Composite Materials Group, Queen Mary University of London, quoted on the Science Media Centre, said:

The safety of buildings constructed with autoclave aerated concrete (AAC) or RAAC depends on various factors, including the quality of construction, maintenance, and the specific conditions they are exposed to.

Over time, if not properly maintained, these materials can deteriorate, potentially leading to structural issues. However, not all buildings made with AAC or RAAC are inherently dangerous. It is crucial to assess the condition of each structure individually to determine any potential risks.

We have invested in our school estate

Our record on capital spending on schools is very different to the approach taken in England:

  • in England, education building funding has declined by around 50% in real terms since 2010
  • in Wales, education capital funding has increased by around 23% in real terms over the last decade

A report by the National Audit Office (2023) found the deteriorating condition of school buildings in England was damaging pupil attainment and teacher retention. In Wales, the Audit Office’s key finding was that the Welsh Government was managing its school building programme well.

Wales has had an extensive programme for the refurbishment and building of new schools and colleges, upgrading and replacing those which are most in need of replacement for safety and quality reasons.

Our Sustainable Communities for Learning Programme (formerly called 21st Century Schools and Colleges) is delivering the biggest new school and further education building programme in Wales since the 1960s to address an ageing estate. More than £2.35 billion has been targeted towards new-build and major refurbishment projects.

And, over the last four years, we have invested £203 million to support local authorities and further education institutions to maintain schools and colleges.

How much will it cost to deal with RAAC in Wales?

There is no overall estimate about what the cost of dealing with RAAC is going to be over the next few years. 

In some areas, for example Withybush Hospital, we have funded the plans in place to respond to concerns that have been identified. In other areas, surveys are being carried out and plans are being developed.

Safety is our top priority and it is the main responsibility of all public bodies to maintain their buildings in a safe condition.

The UK Treasury has said that there will be no new money to deal with RAAC.