In the heart of Peterborough town centre, 130 new residential units have been added above an existing two-storey commercial building.
The existing post-war structure uses internal steel framing and load bearing masonry to the perimeter, and has been heavily modified and extended in recent years. A full historic desk study and extensive site survey were used to form our structural analysis and build a 3D model of Bridge Street.
Access to the ground floor was prohibited and no structure could pass through the existing first floor slab, meaning that existing foundations had to be used and balanced with historic values. In locations where the load was increased, piles were tested and back analysed.
Converting a historic masonry structure from two to five storeys required a novel hanging frame to be designed to support the external 8m wide perimeter bays in the event of a catastrophic explosion blowing out all of the perimeter walls. Section sizes were reduced through the specification of a two storey Vierendeel truss being constructed from the existing internal column bays.