Westminster City Council granted planning approval for the 1 St James’s Square scheme in October through delegated powers, the practice and Hong Kong-based developer Super Expert Investments Limited announced this week – almost two and a half years after plans were first submitted.
The retrofit-led plans will overhaul the inside of an existing, 1990s six-storey structure while adding two more storeys. It will deliver 11,000m² of office space and insert external garden terraces at the seventh and eighth floor levels as part of biodiversity upgrades. The façade will be made of Portland stone and is designed to optimise energy use.
The all-electric building will also include a ventilation system, air-source heat pumps, photovoltaic panels and a green roof.
Fosters’ scheme is aiming to exceed GLA targets for embodied and operational energy and meet the highest sustainability targets, including BREEAM Outstanding, NABERS 5.5* and WELL Platinum.
Fosters head of studio Luke Fox said: ‘Working as an integrated team, which includes our in-house sustainability experts, we are preventing the building from becoming a stranded asset. The decision to retain as much of the existing structure as possible saves embodied carbon, while the introduction of a new breathable façade gives the building a brand-new lease of life.’
The approved scheme is a revision of proposals submitted in May 2023. Updated designs were submitted earlier this year, making minor amendments to the massing, façade design and landscaping.
1 St James’s Square was formerly BP’s global headquarters and, before that, was home to Swedish telecommunications firm Ericsson. Garnett Architecture carried out an interior refurbishment for BP in the early 2000s.