More than 40 classrooms across three Suffolk schools have had to shut down due to autoclaved aerated concrete.
Last week, the Department for Education (DfE) told schools to close buildings that are constructed with RAAC over safety fears and has identified four schools in the region: Hadleigh High, East Bergholt High, Claydon High and Farlingaye High School.
Three of the schools are under the Penrose Learning Trust.
The CEO of the trust, Sarah Skinner, confirmed that 12 classrooms were impacted at East Bergholt High School, 16 classrooms and a gym at Hadleigh High School, and 14 classrooms and a staff room at Claydon High School.
Ms Skinner said she has been "incredibly busy" trying to sort timetabling, obtaining temporary accommodation, issuing letters to parents and retrieving resources from restricted areas.
She said: "Each school has a slightly different return pattern. All schools will have students from Thursday in some form or another.
"There will be some remote learning until temporary accommodation arrives.
"Parents got a letter informing them of concerns on Friday, and subsequently, all parents have a letter regarding return to school detail.
"Both Essex and Suffolk local authorities have been very proactive in trying to help us and our DFE caseworker has been excellent at communicating with us."
The trust’s next step is to let surveyors into the restricted areas of the schools to establish what works will need to be done to resolve the issue.
New information has come out for parents of students attending East Bergholt High School.
The school is in the process of obtaining six temporary classrooms, and it is unlikely that it will fully reopen to all year groups within the next three to four weeks.
The letter to parents reads: "Given the reduced number of classrooms that we have available until the temporary classrooms arrive, we will only be able to accommodate four year groups in school on any given day.
"Students who are not in school will have their lessons delivered online via Google Classroom."
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