The Earnshaw Building project is worth £83m and involves demolition of Castlewood House close to the Centre Point tower at Tottenham Court Road.
Skanska will build a large 11-storey office building with retail and restaurant use and 18 apartments in an adjacent separate building.
Skanska will also install the mechanical, electrical, and public health services for the development, which is targeting BREEAM Outstanding for the commercial office space and BREEAM Excellent for the rest of the development, as well as a WELL Core and Shell Gold certification.
Construction work starts in May and is scheduled to complete in December 2022.