Safety checks ordered amid fears of defects in thousands of schools

Exclusive Investigations into structural concerns over postwar buildings

- Sally Weale

Ministers have ordered intrusive structural surveys of a group of postwar school buildings in England amid concerns about hidden defects that could lead to structural failures.

After the reinforced autoclaved aerated concrete (Raac) crisis, which closed schools and prompted mass inspections, the government is concerned about thousands of "system-built" school structures that could pose a safety risk.

A report by the National Audit Office last year identified 3,600 system-built school blocks out of a total of 13,800 that "may be more susceptible to deterioration".

After months of delays, contractors have finally been appointed to investigate the buildings, which were constructed between 1945 and 1990 and have outlived their design life.

Experts said it was almost inevitable that some schools would be found not to meet safety standards and would need to close.

The revelation comes as part of a Guardian investigation into the dilapidated state of public buildings in England, with analysis finding thousands of schools, hospitals and courts in need of urgent repair.

In some cases they pose a risk of serious injury.

Construction experts say part of the problem is that so little is known about the methods and materials used to erect the "system-built" schools cheaply, at speed and often with few records kept after the devastation of the second world war.

The Department for Education (DfE) has previously identified Laingspan and Intergrid system builds as potentially problematic after two urgent school building closures. One followed the collapse of a wall and the other the identification of severe structural weaknesses.