In early 2018 CDS were appointed by O’Keefe Demolition Ltd to design the external support scheme for the retained corner façade on this project, as well as providing support to one of the party walls and to the existing basement walls.
The façade retention scheme comprised two braced structural steel towers, with portalised frames over the footpaths and with the inner legs extending into the basement vaults. Reinforced concrete strip foundations provided support to the towers, with additional mass concrete being cast to provide the required kentledge weight. CDS completed the Approval in Principle (AIP) process for this scheme, to satisfy Westminster City Council.
At lower levels the party wall had a return wall at each end. At these levels steel walings were used to support the party wall, with the waling ends being fixed into the return walls using metre long resin fixed anchors. At the higher level the party wall was supported using steel walings and soldiers supported by flying shores extending across the site to the top of the two façade retention towers. This support arrangement later allowed the works on the new basement to proceed unimpeded.