New hotel adjacent to Tower of London
Providing structural, geotechnical and civil engineering design services, Ramboll supported the project from inception to completion and worked with the client and then the contractor through the detail design stage. Located within a UNESCO world heritage site, CitizenM Tower Hill interfaces with the original Roman City Wall and Tower Hill Underground station. A critical component of the project’s success was the management of the existing site’s assets, requiring close liaison with other key stakeholders including English Heritage and London Underground.
Offsite constructionOffsite construction was integral to this successful conversion from a five storey 1960’s office block to a nine storey hotel. Providing lightweight construction, modular steel pods enabled Ramboll to design a solution that ensured the new load paths from the hotel compared favourably with the former loads from the office and the capacity of the existing station structure.
Not only did modular steel pod construction facilitate the addition of a further four storeys to the hotel, it made it possible for the architect to include Portland stone cladding on the façade (a requirement only stipulated at the planning approval stage). This sympathetic addition ensured the hotel would complement its surrounding environment – an important consideration for the planning authority.
Bringing speed and assured quality to the construction, the modules were manufactured, fully fitted and sealed in Poland. Stored offsite in the Port of London dockyards, they were brought into the City and placed in situ overnight.
Over 3½ months, the 370 modules were typically installed at a rate of eight units per night, with the facility to install up to 14 units. The overnight installation programme minimised disruption to London’s busy streets. The modular steel solution significantly reduced site waste and consequential environmental impacts from the construction. This offsite constructionmethod reduced the workforce needed on this very confined city site, made for a safer working environment onsite and reduced impact on local city workers and tourists.
Meeting the client brief to ensure a sound night’s sleep for its guests, Ramboll identified the need to isolate vibrations from the underground lines beneath. Our advanced engineering team developed a strategy for achieving this without significantly affecting the architect’s design.