This is an increase of 17 compared to previous figures for buildings affected by reinforced autoclaved aerated concrete (Raac).
That number could rise, as Education Secretary Gillian Keegan said there could be a “handful” of schools where Raac has yet to be identified.
Forty-one affected schools and colleges have temporary buildings on site.
In cases where specialized classrooms are affected, such as science labs, nearby schools may be asked to share facilities.
Despite the increase in the number of affected schools, many students in the affected schools have been able to return to full-time in-person education since the most recent list was released.
The Department for Education (DfE) said three of the 231 affected schools are teaching in a hybrid environment, with students splitting their time between face-to-face and remote learning.
The government said no schools are still operating fully remotely.
The DfE said it will update the list – currently accurate as of November 27 – every two weeks. But the previous list was announced on October 19.
‘Mitigating is the right approach’
Speaking to the Education Select Committee on Wednesday, Ms Keegan said all schools suspected of having Raac had now responded to the DfE questionnaire.
Where it is safe to do so, the DfE is trying to keep existing school buildings open with mitigation measures, such as raising ceilings with wooden beams.
“We have around 110 schools where we think mitigation is the appropriate approach rather than temporary buildings,” said Permanent Secretary Susan Acland-Hood.
Raac is a lightweight material used primarily in flat roofs, floors and walls from the 1950s to 1990s. It is a cheaper alternative to standard concrete and has a lifespan of about 30 years.
In June, the National Audit Office reported that years of inadequate funding had increased the risk of building collapse.
Are you affected by the issues raised in this story? Contact.
Over the summer, a Raac panel that would have been classed as “non-essential” collapsed at a school in England – leading to a final decision to act and a scramble before the start of term.
Earlier this year, National Headteachers’ Association general secretary Paul Whiteman said disruption for many pupils, parents and staff was now a “real concern”.
Members reported that the DfE’s initial response had been “mostly good”, he said, but many were still waiting for temporary classrooms to come on stream, with some expected to wait “more than six weeks”.
National Education Union general secretary Daniel Kebede said: “Parents and the public need to be reassured that the Ministry of Education has this issue under control.”
Schools in 17 local authorities in Scotland were found to have Raac and five schools in Wales were affected – two in Anglesey, one in Conwy, one in Denbighshire and one in Newport.
As of October 19, surveys were planned for 120 schools across Northern Ireland to test the strength of the concrete, the Education Authority said.
Note all installations with Raac have been confirmed on November 27, 2023 as published on the government website on December 6.