A building at Dannevirke South School has been condemned, displacing 175 pupils.
A report by Kell Engineering shows block A, which encompasses seven classrooms, the administration office, teacher resource rooms and the library, has structural damage in the roof which has the potential to see the ceiling come crashing down.
"This has been a big shock for all of us and it has come out of the blue," South School Principal Stephen Snell said. "Thankfully, the problems were picked up in the check."
The structural damage was identified during a routine check as part of the school property development plan but it was not a new problem, Mr Snell said.
"We found out at 4pm on Friday from the Ministry of Education that the building was not safe for our pupils and the board took immediate steps to close the affected buildings. There are serious issues with the roof structure which appear to have occurred because of the many alterations done over the years."