Office scheme to transform Old Street Roundabout’s Inmarsat Building

Islington council has approved KPF’s plans to transform the Inmarsat building on Old Street roundabout into a 35-storey office tower.

The Shoreditch scheme proposes using the 1990s office building at 99 City Road as the base of a 154m tower containing 65,000 sq m of office space.

Around two thirds of the existing building’s structure will be retained, including the foundations and basement, with a new facade and a new core to be inserted to support the tower.

Designed for developer Endurance Land, it aims to revive the area’s struggling tech cluster, known as the Silicon Roundabout, which has seen a number of high profile firms leave in recent years.

It will also include a triple height event space on the ground floor and a large new public square leading onto Weston Williamson & Partners’ new Old Street station, which is currently being built by contractor Morgan Sindall and is expected to open in 2024.

Councillors voted yesterday evening to back the planning officers’ recommendation to approve the tower following two hours of deliberations.

Historic England objected to the scheme on the grounds of its on views of nearby buildings including the grade I-listed Wesley’s Chapel and the grade II*-listed Armoury House.

The planning officers’ report admitted the height of the tower would harm the heritage sites and also departed from the borough’s development plan but said this was offset by the scheme’s “exceptional” design, new public realm and the provision of  4,300 sq m of affordable workspace.

The report said: “It is considered that on balance, the harm created by these proposals, inclusive of the tall building that represents a departure from policy, is outweighed by the scheme benefits, notably exceptional design and fundamental improvements to townscape and public realm, excellent sustainability and energy performance, generous community facilities and employment and training benefits including affordable workspace.”

Endurance Land chief executive Jonathan Fletcher described the design of the tower as an “incredible achievement”.

“The redevelopment will deliver a landmark scheme that’s tailored to Islington and Old Street, drastically improve the building’s sustainability credentials, offer generous community benefits, and unlock the potential of the site,” he said.

The project team currently includes structural engineer AKT II, Atelier Ten on MEP, Publica on public realm design, planning consultant DP9, townscape consultant Montagu Evans, Sweco on vertical transport, project manager Avison Young and cost consultant Arcadis.

A main contractor is expected to be appointed in the coming months, with construction to start once Inmarsat, a satellite telecommunications firm, moves to new premises next year.