Core Five marks practical completion of £200m One Exchange Square retrofit at Broadgate

Core Five has announced practical completion of One Exchange Square, the 13-storey retrofit of 175 Bishopsgate on the Broadgate Campus in the City of London, having been involved since feasibility work in December 2020.

The consultancy said it had provided cost consultancy and employer's agent services on behalf of Permodalan Nasional Berhad, working alongside LaSalle Investment Management and M3 Consulting.

Core Five said the completed building provides 440,000 sq ft of office and retail space, retains 94% of the original structure and reuses the facade, with planting and terrace gardens throughout. It said it looked forward to the building welcoming its first occupiers.

Core Five's role

Core Five has been involved since the feasibility stage in December 2020, according to its own account of the project. Its employer's agent team joined in August 2022. The City of London resolved to grant planning permission for the scheme, Gillespies reported.

Multiplex started on site in February 2024, when Core Five valued the scheme at £200m and described it as 430,000 sq ft of offices and 17,000 sq ft of retail. John F Hunt Group held the demolition and enabling contract.

The building topped out in the week of 26 June 2025, Core Five said at the time. Structural engineer Heyne Tillett Steel said in August 2025 that the building was set to complete in early 2026; Core Five has now announced practical completion.

Core Five's own figure for the amount of structure retained has moved over the life of the job: it said 90% at start on site in February 2024 and 94% at completion. Facade contractor Staticus gives over 90% on its project page.

The retention case

Fletcher Priest Architects designed the scheme, which Gillespies described as an extensive reconfiguration of an existing 1980s post-modern office building. The consultant team at planning included Core Five, Sweco, Heyne Tillett Steel, DP9, Silver DCC, GIA Equation and QCIC.

Heyne Tillett Steel said retaining 94% of the existing structure saved about 12,000 tonnes of carbon compared with an equivalent new-build office, and that the completed building would have 50% less embodied carbon than a typical office of comparable size. It put the structural embodied carbon at 55 kgCO2e/m2.

The building sits over railway platforms and tracks, which ruled out new foundations, the engineer said. Existing shallow and pile foundations were reused without strengthening, with their capacity justified through a managed process with Network Rail.

The redevelopment added 7,710 sq m of office and terrace space, according to Heyne Tillett Steel. It said 20 tonnes of the new steelwork was reclaimed from other demolition sites and 85% of the steel procured was electric arc furnace steel, beating a 70% benchmark.

Staticus delivered the 14,500 sq m facade with Eckersley O'Callaghan and Fletcher Priest Architects, describing the package as its largest UK subcontract to date. It said 75% of the existing facade was to be reused and enhanced, with Juliette balconies on floors 2 to 12 and full-height openable windows, and that it expected to start installation in September 2024.

Gillespies designed a series of stacked landscaped terraces and winter gardens for the building. Core Five said at start on site that the scheme targets BREEAM Outstanding, NABERS 5 star and WELL Platinum.

Occupier signed

FTI Consulting has disclosed an agreement for leases at the building. FTI Consulting, Inc. told the US Securities and Exchange Commission that on 21 November 2025 it entered an agreement for leases at One Exchange Square, 175 Bishopsgate, London EC2M 3TW, with PNBJ I Limited as landlord.

The premises comprise about 80,664 rentable sq ft, with an option to increase to about 102,828 sq ft, according to the filing. FTI put the aggregate rent over the term at about $115m, or $145m with the expansion space.

The leases run for 15 years, subject to a break option, and FTI expects to take possession on or about 25 September 2027.