10 Salisbury Square, London EC4

John Robertson Architects’ proposals have submitted a planning application for the sensitive transformation of St Bride’s House at 10 Salisbury Square to the City of London Corporation. The project will deliver 52,500 sq ft of much-needed Grade-A office space at the heart of the City’s emerging Justice Quarter. As the first development from Original Works, a joint venture between Simten and Invesco Real Estate Europe Fund III, the scheme reflects a bold vision for sustainable and heritage-conscious urban renewal. Retaining over 90% of the existing structure, the retrofit-first approach dramatically improves energy performance while enhancing the building’s relationship with its historic surroundings, including the adjacent Grade I listed St Bride’s Church.

In a further commitment to circular principles, the scheme makes innovative use of reclaimed façade panels from the existing building fabric. Salvaged elements are reintroduced as elevations to the new extension - while avoiding the carbon costs of new materials. The removal of the elements from the existing floors increases window sizes, enhances daylight access, and improves occupant wellbeing. In doing so, the existing façade is reimagined as a refined, modern counterpart of its former self: updated to meet today’s functional and environmental standards yet still rooted in its original architectural language. These careful interventions allow the building to express a renewed clarity and purpose, aligning seamlessly with its sensitive historic context.

The design prioritises occupant wellbeing, low-carbon outcomes, and biodiversity, with features such as openable windows, rooftop gardens, and integrated rainwater reuse. Set within the Fleet Street Conservation Area, the revitalised building will repair the urban fabric, honour local heritage, and support the transformation of Salisbury Square into a more inclusive, vibrant and climate-resilient part of the city.