The expansion, which will boost capacity at the facility in Barrhill Road from approximately 1,600 to 2,000, was approved by councillors earlier this year.

A report, which was considered at last week’s education and children’s services policy board, provided an update on the project and confirmed Renfrewshire Council’s plans to “create additional flexibility” and space in the interim, Glasgow Times reports.

A modular unit, which has been used as Paisley Central Library before its move to High Street, will be cleared out and relocated to the high school in late November. It will be repurposed and operational by April 2024.

The report, authored by head of education and interim chief education officer Julie Calder, said: “In May 2023, the education and children’s services policy board approved a 400-pupil extension to the capacity of Park Mains High School, and to cap that school’s total capacity at the extended 2,000 capacity figure.

“It’s anticipated that the extension will be in place and operational for June 2027.

“To create additional flexibility and capacity in the interim, a modular unit being used at Paisley Library but which is no longer required there as a result of the opening of the new learning hub will be moved to Park Mains High School over the weekend of November 25/26.

“Once repurposed this will be operational from April 2024, and will be able to accommodate up to 156 pupils. The modular units will provide for five classrooms, staff toilets, pupil toilets and an accessible toilet.

“The high-level cost estimate for an extended building to the school is circa £30m.

“Discussions are ongoing regarding the obligation of BAE Systems who, under the existing Section 75 agreement, are required to contribute towards the expansion cost.”