250 City Road: Precast Concrete Innovations

250 City Road is a mixed-use residential development in London, where Ramboll played a pivotal role in transforming the construction approach. Designed by Foster + Partners and completed in 2018, this landmark project spans over 70,000 square meters (m²), including six structures and a striking 38-storey residential tower.

Ramboll’s key challenge was to convert the original in-situ concrete design into a precast concrete structure, optimizing both construction time and quality while enhancing the project’s sustainability. Initially designed with a traditional in-situ concrete scheme, Ramboll, in collaboration with Expanded Ltd, introduced an innovative precast solution. This approach leveraged Design for Manufacture and Assembly (DfMA) principles, allowing offsite manufacturing of key structural elements such as lattice slab systems and twin wall concrete cores. The result was a significant reduction in the construction programme, while maintaining high-quality finishes.

Ramboll’s solution not only addressed the project's structural complexity but also contributed to a smoother construction process. By reducing onsite work and material waste, the precast alternative minimized the environmental impact, aligning with Ramboll’s commitment to sustainable development.

Key outcomes of included a shortened construction timeline utilising DfMA, while providing a superior concrete finish, setting new standards of residential construction.