Barr will refurbish Castle Primary School and also build a new nursery department.
Barr was the lowest bidder of 16 companies that tendered for the contract.
Refurbishment of the existing school includes partial demolition of the gym hall to build an extension for a new dining block, gym and storage area.
The new build nursery comprises approximately 620 square metres gross internal floor area with a covered link to the existing school.
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