Navigating unsafe concrete in school buildings

Why is the presence of Reinforced Autoclaved Aerated Concrete (RAAC) in buildings such a problem, and how are schools dealing with the issue? We examine the situation

Schools with Reinforced Autoclaved Aerated Concrete (RAAC) confirmed in their buildings have been told to vacate and restrict access to the spaces until the structures can be made safe. This has caused disruption to many schools, with many having to utilise temporary accommodation, and some switching to a mix of home and school learning.
    
As of 16 October, 214 schools were confirmed to have RAAC present. Of these, 202 settings are providing face-to-face learning for all pupils and 12 settings have put hybrid arrangements in place.
    
But what is RAAC, and why does it pose a problem?

What is RAAC?

RAAC is a lightweight form of concrete used in schools, colleges and other building construction from the 1950s until the mid-1990s. It is predominantly found as precast panels in roofs, commonly found in flat roofs, and occasionally in floors and walls.  
    
It means it may be found in any school and college building that was either built or modified in this time period. The Standing Committee on Structural Safety (SCOSS) has noted that: ‘Although called “concrete”, RAAC is very different from traditional concrete and because of the way in which it was made, much weaker.”

Why is it only being dealt with now?

In 2017, the Standing Committee on Structural Safety was asked to investigate RAAC after a school roof collapsed.
    
In 2018, another roof collapsed at a Singlewell Primary School in Kent, which prompted Kent Council to write to other local authorities warning them to check for RAAC in their schools.
    
Since 2018, the Department for Education said that guidance has been clear about the need to have adequate contingencies in place in the eventuality that RAAC-affected buildings need to be vacated at short notice.
    
In 2022, the Department for Education sent a questionnaire to all responsible bodies, asking them to provide information to help them understand the use of RAAC across the school estate.
    
In 2023, the Health and Safety Executive declared: “Raac is now life-expired. It is liable to collapse with little or no notice.”
    
With this mounting evidence and information, the government announced that any school with RAAC present should vacate the building at the start of the new academic year in 2023.

Identifying RAAC

In many cases, RAAC panels can easily be identified if a building’s structure is not covered by finishes or decoration, such as ceilings. RAAC panels are most commonly found on flat roofs, but they may also be found in pitched roofs, floors or walls.
    
RAAC panels are light grey or white in appearance and the underside of the panels will appear smooth. The inside of the planks will appear bubbly, often described as looking like an Aero bar. Unlike traditional concrete, there will not be visible stones in the panels.

If you have drawings from the time the building was built or modified, you should review these. Common manufacturers of RAAC panels are Siporex, Durox, Celcon, Hebel and Ytong.
    
RAAC panels typically have a chamfer along their edge meaning there is a distinctive V-shaped groove every 600mm in the surface of the roof, floor or wall.
    
RAAC panels are very soft – if you press a screwdriver, screw or nail into the surface of a RAAC panel, you will be able to make an indentation. If there is a surface covering to the panels you should not try to make an indentation as the covering may contain asbestos.
    
RAAC panels may bow or deflect. From the underside of the roof or floor you may see a ‘gap’ between two adjacent panels.
    
If unsure, assistance should be sought from an appropriately qualified building surveyor or structural engineer with experience of RAAC to confirm if RAAC is present in any of the buildings.
    
If RAAC is confirmed, a school must then inform the Department for Education (DfE) via the DfE Capital Portal. Prior to further investigation, schools will need to gather and supply relevant information about their buildings and list all spaces where additional measures will be required to enable the surveyors to see the surfaces clearly.

Vacating buildings

For schools that have RAAC confirmed, the Department for Education has assigned the school with a ‘case worker’. DfE guidance says that if a school has insufficient accommodation once the areas with RAAC are taken out of use, schools should look to find emergency accommodation or temporary accommodation until the building has been made safe through structural supports.
    
This may be space in a nearby, local school, college, or nursery, or semi rigid temporary structures that can quickly be brought to site. It may also be space in a community centre or empty local office building. Schools can also procure temporary accommodation if there is space.

Funding

The DfE has announced that it will fund refurbishment projects, or rebuilding projects where these are needed, to rectify RAAC in schools and colleges for the long term.
    
It will also fund emergency mitigation work needed to make buildings safe, including the installation of alternative classroom space where necessary. This is in addition to any SCA or funding through CIF for financial year 2024 to 2025. If a school is able to commission a survey more quickly, they are to notify the DfE for review. It will be funded unless unforeseen issues are identified.

Installing temporary buildings

For schools installing temporary buildings, they will be known as “Class CB”, which is a time-limited right which expires on 24 October 2026. It allows schools to install temporary buildings, without having to submit a planning application to the local planning authority, subject to limitations and conditions. This does not affect other consents that may be required, such as building regulations, which continue to apply.
    
Schools must notify the local planning authority and the relevant fire and rescue authority that they are using class CB to provide temporary buildings. They must provide a written description of the development, a plan showing the development, the expected start date for development, as well as the total floor space (in square metres) of school buildings that have been vacated due to RAAC and the total floor space (in square metres) of the temporary buildings being provided.
    
Temporary buildings cannot be installed within five metres of a boundary with residential land and cannot exceed two storeys or nine metres in height. They cannot have a combined floor space which exceeds 125 per cent of the combined floor space of the parts of buildings vacated. The buildings must be placed to minimise, as far as practicable, any reduction in the amount of land used as playing fields and space available for parking or turning.

What are schools doing?

Honywood in Coggeshall, Essex, is one of the schools most severely affected by the RAAC issue. Almost half of the entire school estate has been ruled unsafe, including 22 classrooms, toilets, the counselling room, medical room, and other offices.
    
The start of term was delayed by a day while the areas were tapped off and a learning continuity strategy was devised. The year sevens were prioritised for face-to-face learning, alongside year 11s who will sit their GCSEs next summer. With no more than three year groups allowed on site at any one time, the rest are learning from home.
    
A temporary school was built in six weeks and is located in the sports field. It is expected to be in place for a year while the RAAC is being dealt with. The new site has 21 classrooms and a toilet block.
    
While the costs of the temporary building is said to be covered by the Department for Education, the school had to fund raise for certain unexpected costs, such as remote learning tools and off-site spaces, headsets for teachers, additional toilets and the movement and storage of displaced equipment.
    
Roding Vally High School in Loughton, Essex, was found to have RAAC panels in the roof of the building that consists of 18 classrooms, the canteen and kitchen, as well as staff workspaces. This has resulted in the school implementing a two week rota for onsite and home learning. Temporary classrooms have now been installed on the school site comprising nine classrooms and a toilet block.
    
Sheffield City Council have raised concerns that they may not be reimbursed for money they have used to remedy RAAC in Abbey Lane Primary’s roof in July, having used cash from the £3.5 million for capital projects they receive each year from the Department for Education.   
    
The council began a £620,000 project before the announcement was made that schools with RAAC were to close and the government was to fund the projects.
    
A spokesperson for the council said: “We asked the DfE for retrospective funding, but at this stage there are no retrospective reimbursements for affected schools where RAAC has been removed or replaced and paid for out of existing condition funding.
    
“If we don’t receive reimbursement, we will have been financially penalised for acting at an early stage. We were putting our children’s safety first before it became a critical national issue.”