Just days before the government suddenly ordered schools in England to close buildings at risk of collapse due to the presence of reinforced autoclaved aerated concrete (Raac), another – somewhat smaller – school buildings story hit the headlines.
Three virtually brand-new schools were suddenly told to close by the Department for Education (DfE) with immediate effect because of safety fears. A further two primary schools, it later emerged, had to be demolished before completion.
The schools minister, Nick Gibb, was forced to admit there were issues with the structural integrity of the buildings and said they may not be able to withstand extreme events, including severe weather or being hit by a vehicle. Raac had played no part.
While school buildings affected by Raac are generally much older – the material was widely used in the UK from the 1950s to the 1990s – these condemned school buildings were modern and built using the latest modular, off-site construction methods now favoured by the government. Yet they too failed.
As a result, Sir Frederick Gibberd college in Harlow, Essex, which opened in 2021 having cost £29m to build, was ordered to close its main building and sports hall. Buckton Fields primary school in Northampton, which opened two years ago, was advised not to reopen, and Haygrove school, an academy in Bridgwater, Somerset, was told to close its main building, only completed in October 2020.
With the condition of the school estate in England fast deteriorating, the DfE launched a £3bn programme in January 2020 to upgrade using “modern methods of construction”, involving off-site construction of modules that would be transported to site and then assembled.
The benefits of such a system are that construction is quick – limiting disruption for pupils – and cost-effective. Building sites are much safer as much of the work happens off-site in a factory, and the quality is likely to be higher as it is made in a controlled environment. The closure of these new schools suggests it is not totally foolproof, however.
The DfE identified a specific contractor, Caledonian Modular, which was involved with all the affected schools and has since gone out of business. It is now reviewing other DfE contracts, as well as those in other departments, to identify where Caledonian Modular may have been involved.
Dr Lee Cunningham, a reader in structural engineering at the University of Manchester, said: “First and foremost, inherently there should not be a problem with modular construction if it’s done right.” Any issues are more likely to arise from construction defects, rather than design.
“Prefabrication remains attractive, not just for cost and speed of construction, but also for safety. In terms of site safety, the more that you can do in a controlled environment, in a factory, the better the quality of the product, but also, usually, the safer the processes are.”
Michal Drewniok, a lecturer in civil engineering at the University of Leeds, agreed. “In general, modular construction is a good and efficient method of construction,” he said. “The quality of every single element is much better than elements that are actually made on the construction site. What really matters is the precision of assembling the different parts and proper maintenance.”
