A new quadrangle for St John’s College on a very challenging site close to listed medieval walls, protected trees and listed buildings. The building provides student accommodation, café, gym, library, party room, music room, archive and teaching spaces, and includes a new basement over the entire plan of the building.
Archaeological investigations during the Enabling Works uncovered a suspected Viking mass grave, and a Neolithic ‘henge’ considered one of the most significant archaeological finds in Oxford in recent decades.
An intricate in-situ concrete framed structure was adopted to accommodate the complexities of the site, incorporating white precast columns and walls, and feature staircases. Four precast concrete stairs provide access between the floors, with the two North stairs linking only the upper floors. Consequently, the outer stone clad precast walls of the North stairs do not reach the ground, instead being hung from a cruciform transfer structure at high level. After the external walls of the outer shell received their cladding, a careful sequence of working was required to post-tension the hanging rods and transfer the weight of the structure into the cruciform, lifting it off the temporary supports.