Sarnia's new Great Lakes Secondary School won't open now until September of next year.
Lambton Kent District School Board Superintendent of Business Brian McKay said the former St. Clair Secondary School site won't be ready, as hoped, for student occupancy in January.
The second project delay comes following a meeting with the Murphy Road site contractor, Concord-based Jasper Construction.
McKay said paving is a major issue.
"As we try to enclose the addition, we're becoming concerned on the timing when the asphalt plants might close," said McKay. "Without getting the paving done, clearly there's no ability to move onto the site between the semesters. The asphalt plants tend to close late fall, so potentially late November."
The original timeline called for the renovation and addition to be complete in time for the start of school this year.
McKay said the delays are not expected to impact the project's $25 million capital budget.
The education ministry provided $10.3 million for the new school that will feature a new auditorium, Indigenous community room, updated classrooms, and accessibility improvements.
Students remain at the former SCITS site on Wellington St. until upgrades are complete.
-With files from Dave Dentinger