PORTSMOUTH City Council has appointed a local construction firm to refurbish The Harbour School.
The school, to be situated at The Vanguard Centre in Cosham, will undergo an extension by Portsmouth-based Mountjoy Ltd.
The works will provide classrooms, office and circulation space with modern toilet facilities.
External landscaping work will also offer alternative teaching spaces for staff and new access arrangements.
The project begins this spring and will take approximately 34 weeks to complete.
The Harbour School educates children and young people with Social, Emotional and Mental Health needs (SEMH).
The organisation has bases in Tipner and Stamshaw and is moving from a site in Fratton.
This new school will cater for up to 110 pupils.