The Old War Office is an iconic 580,000sq. ft. Grade II Listed building on Whitehall, in the heart of London. The disused former Government building of national heritage importance is being sensitively repurposed to create a five star 125-key luxury hotel and 85 studio-to-five-bedroom apartments.
Structural Engineer: Elliott Wood
Project Value: Demolition 10 Million
Contract Value: 92 Million
Sector: Demolition, Structual Alteration, Temporary Works
Date of Completion: June 2020
Tilley and Barret, as part of the Toureen Group Principal Contractor for the site, was appointed to undertake the complex demolition of the multi-story office sections. The complicated demolitions were completed on a floor by floor basis, whilst also undertaking major structural alterations. These included the removal of significant load bearing walls, which in some cases spanned three floors up to a meter thick. Whilst removing we installed purpose built permanent frames that weighed between 5 and 25 tons. Temporary works such as RMD Frames, temporary steel frames and pinning were also installed, all within a very constricted operational site space.
Due to water ingress, the roof had been condemned. Tilley and Barrett completely removed the roof structure and provided a temporary crash deck throughout the underside of the building. The crash deck was not only capable of taking the weight of the roof slab under demolition, but also the weight of our machines travelling above, materials for the task and the work force. The deck also provided a complete external roof, formed from traditional tube and fitting scaffolding with an enviro wrap, along with water proof protection.
During demolition, the amount of concrete and hardcore that had to be removed was significant. To maximise the efficiency of its removal, Tilley and Barrett designed a bespoke waste chute. This was fabricated and installed on the external side of the building which allowed the material to be transported by skid steer across the roof, and dropped into a loading gantry position to be carted away from site.
Using our experience and expertise, Tilley and Barret installed multiple door openings and formed new rooms on a major scale, including the installation of circa 1200 lintels and removing thousands of tons of brick and concrete on mass throughout the historic building.
Being a Grade II listed building, our operatives had to install protective covering and navigate around specific listed structures that were steeped in history, delicately packaging and relocating numerous artifacts that will to be used again once the building has been transformed.
At its peak Tilley and Barrett had 75 operatives working on the re-modification and demolition of the Old War Office. This included work taking place in unison over multiple floors with a range of different expertise and specialist task teams.