48 Leicester Square, London, W1

The John F Hunt team undertook a highly intricate demolition and reconstruction programme centred around a fully engineered four-sided façade retention system in one of London’s busiest and most constrained urban environments. Due to extensive modifications since its original construction, internal jacking and load testing needed to be carried out to facilitate the demolition.

Spanning 180 metres in length and safeguarding five storeys of historic Portland stone, this scheme demanded exceptional precision and proactive stakeholder coordination. To provide the most efficient programme, the initial scaffold was cantilevered out from the top floors. This enabled the roof demolition to commence whilst the façade retention system was installed.

At the heart of the project was the design and installation of a robust façade retention system constructed from 250 tonnes of fabricated steelwork and supported by 400m³ of kentledge.

Extensive structural investigations and load testing were undertaken early in the programme to understand the building’s movement since its original 1923 construction, informing a safe and efficient demolition strategy.

Internal demolition was carried out floor by floor, including the installation of 3m deep piling, while a bespoke cantilevered scaffold system enabled the advanced removal of the existing roof structure.

To support statutory upgrades, our team constructed three temporary UKPN substation bases and integrated the foundation for the new substation directly into the kentledge formation for the façade towers.

RC crane bases were installed at lower ground level to facilitate the erection of two tower cranes, essential for material handling within the confined city centre site.

Superstructure works included the installation of an RC raft slab with below-slab drainage, attenuation, and five pumping stations, all delivered under a Grade 3 waterproofing strategy. Additional elements included a new RC liner wall, two jump-formed cores, composite metal deck flooring and a precast RC stair installation.

Working amid significant utilities constraints, including major gas services, BT communications equipment, a live substation and critical sewer infrastructure, we implemented specialist temporary works, such as demolition scaffolds spanning pavement lights and a re-engineered structural ramp adapted into a vehicle gantry.

Our agile resequencing gained programme time by overlapping demolition and construction activities, ensuring minimal disruption to the public realm and uninterrupted access throughout Leicester Square.

Located in one of the busiest parts of the West End, extensive planning, ongoing community engagement, and having a flexible approach to the works were all key factors in its success. The works were completed with very little disruption to the local area and the processes used enabled maximum recycling and reuse of the internal steel frame and concrete floors

With the technical challenges and sensitive location, this project demonstrates our commitment to quality and project delivery, which was highly commended by being nominated as a Construction News Awards finalist.