100 Bishopsgate, London

To support the delivery of a new, 950,000 ft² best-in-class office and retail accommodation across two buildings, as well as a newly created half-acre public square in the heart of London, our team provided innovative piling and retaining wall solutions. 

Due to the significant loads and height of the buildings being constructed as part of the development, we installed rotary bored piles up to 65m deep to act as load bearing foundations, some carrying loads of 40MN. Coring through 60 existing piles and obstructions, we deployed three large rigs and two cranes to maintain pace on the restricted city centre site. 

The scheme also required the installation of 69 of the UK’s largest plunge columns. To enable precise installation of the heavy plunge columns and adhere to design specifications, we developed a bespoke plunge column guide frame – resting directly on the piling platform due to the large weights involved. This top-down method saved six months of the programme time. 

Collaboration with Robert Bird Group and Multiplex were key on this scheme and drove value engineering across 40 design iterations, optimising efficiency and safety factors. Early redesign of secant piles – from 1200mm to 750mm and 1050mm diameter – and amendments to plunge column detailing and reinforcement saved four weeks of potential setback, demonstrating our ability to innovate under pressure.