RSHP submits plans for 54-storey City office tower

RSHP’s proposals to build a 240m tall office building in the City of London’s eastern tower cluster have been submitted for planning.

Plans for the 54-storey 99 Bishopsgate scheme revealing new images of the building were filed with the City of London Corporation earlier this week by developer Brookfield Properties.

The submission of plans is a significant step forward for one of the largest office schemes in the Square Mile, which is currently seeing a concentration of high rise commercial development set to transform the area around Bishopsgate and Gracechurch Street.

The tower would be located on a prominent corner site at the edge of the City’s main tower cluster and is described in planning documents as a “transitional” building aiming to blend the architectural styles of nearby skyscrapers with more traditional buildings to the north.

Its proposed bronze-coloured facade is intended to reflect the mainly brick buildings of the neighbouring conservation area, while its lower levels have been designed to increase public access and permeability with a series of large open public spaces.

> Also read: Is the City set for a new tower boom?

The site is currently occupied by a 28-storey tower built in the 1970s which serves as the UK headquarters of Brookfield-owned contractor Multiplex. This would be demolished to street level from early 2026 with construction of the replacement tower starting at the beginning of 2028 and completing in the third quarter of 2030.

The design of the building has been heavily influenced by plans to save embodied carbon by retaining the existing building’s 2.5m thick concrete foundation raft.

Because this underground structure is not strong enough to bear the weight of the new scheme, the new tower will be supported by a diagrid structure, an external framework of diagonal steel ribs which will wrap around the existing concrete raft.

This means the structural support of the building will be external, with a load bearing “satellite” core containing the main passenger lifts attached to the outside of the tower and a non-load bearing “soft” core in the centre of the tower containing life safety systems and goods lifts.

A standalone cultural building would also be built on the site intending to align with the Square Mile’s vision to become a seven-day-a-week ‘destination city’.

This six-storey block would contain a mix of cultural uses including a ground floor gallery, a multipurpose events hall and creative studios for podcast recording, rehearsals and video editing.

The site neighbours 55 Bishopsgate, a 270m-tower designed by AFK which was approved last summer and will be the City’s third tallest when built.

There is expected to be a significant period of overlap between the two projects, meaning two of the biggest schemes in the City will be under construction at the same time on adjacent sites.

Planning documents for 99 Bishopsgate also include a 57-page construction management plan drawn up by Brookfield subsidiary Multiplex, which is expected to be appointed as main contractor on the job.

Other firms on the project team include T&T Alinea on costs, AKT II on structural engineering, Ramboll on MEP services, Atelier 10 on sustainability, Momentum on transport, GIA on sunlight and wind, Trium Environmental Consulting on environment and Andy Sturgeon as landscape architect.

Planning consultant DP9, communications consultant Kanda Consulting and heritage and townscape consultant The Townscape Consultancy are also on the team.