
Mace says it will not be using fossil fuels during the construction of what it describes as one of London’s largest retrofit projects.
JP Morgan Asset Management has appointed the contractor for a c.£200m revamp of 65 Gresham Street.
The project includes expanding the original early 2000s building from 25,000 sq m to 38,000 sq m, adding four new lightweight floors to the existing eight-storey structure, and creating external terraces and inset balconies on every floor.
Mace said it will prioritise a “reuse-first approach” in this project. This will involve retaining more than 70% of the existing building’s structure, with 95% of materials recycled or reused on site. It is also targeting a 66% reduction in whole-life carbon.

The building will be fossil fuel-free in operation and will use air-source heat pumps for heating, cooling and hot water generation.
Ged Simmonds, managing director of private sector at Mace Construct, said: “This ambitious retrofit project exemplifies Mace’s commitment to sustainable construction, showcasing innovative solutions that reduce environmental impact and set the standard for the next generation of sustainable offices.
“In the past five years, we’ve seen a growing trend in the City of London for sustainability-driven, reuse-focused office developments.”