This project consisted of demolishing an existing building in Vauxhall wedged in a triangle of land between two roads down to street level, leaving a partial basement. Three storeys were rebuilt above the lower ground plus a roof terrace.
On this constrained site, complex foundations and groundworks were largely avoided by reusing the existing massive brick retaining walls as footings. A reinforced concrete capping beam was introduced to cap these walls, tie them together and to act as a spreader beam to distribute the loads of the building into the existing walls. These walls were then internally faced with concrete to provide a clean, dry internal surface. This also meant that the existing brick sewer running just outside the basement line in St. Oswald’s Place would not be disturbed.
The structure consists of load bearing masonry cavity walls supporting steel beams with timber floors. The steel beams generally bear on padstones in the masonry walls. Where there are overhanging bays or balconies, the steel beams cantilever out to support these.
The Tyers street elevation has several openings both at the basement clerestory level and at the ground floor level which means that the remaining masonry wall panels are not sufficient to carry the loads from above. In addition, this elevation has a large cantilever bay protruding over the pavement. The structural solution was to insert a steel frame from the basement capping beam at street level to the first floor. This frame has also been designed to resist in plane lateral loads by frame action due to the insufficient length of masonry wall to resist such loads.