The five were working on the structure on Kier’s £35m contract at the Abraham Darby Academy when it came crashing down.
Academy officials are now writing to parents to explain how the collapse could affect the new term.
The new academy is set to replace the existing school building.
Principal Steve Hawke said: “The existing Academy building is far enough away from the area where the incident happened to remain unaffected.
“I will however, be sending letters to every pupil’s parent/carer to explain the situation and what this will mean for the start of term.”