63 St Mary Axe

63 St Mary Axe Tower © Fletcher Priest Architects

63 St Mary Axe, London | 2023 - Ongoing

63 St Mary Axe is a mixed‑use office tower featuring trees on each of its 46 floors, creating a striking vertical forest. This planted tower introduces a new building typology to the City of London. By selecting trees and shrubs that attract wildlife, the vertical planting enhances biodiversity and fosters a greater sense of well‑being for people, plants, and animals. All of this is achieved within a compact footprint, while enabling green connections to weave through the building in three dimensions.

At the base of the tower, a small pocket park incorporates a former churchyard and a section of the Roman Wall. Designed as a tranquil spot with ample seating, the park is richly planted with shady trees and plants. A section of the Roman Wall within the park will be uncovered and made accessible for viewing. Together with the improvements to the historic churchyard, these interventions create powerful connections to the site’s past, which will be further explained through thoughtful interpretation. In the south-east corner, an auditorium is allowed to spill out into the park, with tables and chairs for school classes. A paved plaza below the tower’s northern canopy allows for regular markets and community events, while planting along the west facade frames entrances to retail and cafés. Throughout, thought has been given to enabling a seamless and welcoming experience between inside and out.

The first three floors of the tower are publicly accessible via planted terraces connected by external staircases that pass through green veils of flowering climbing plants. On the 27th and 28th floor two large roof terraces are planted with shrub and meadow vegetation for the enjoyment of office tenants, with framed views across London.

The project supports the creation of Cool Routes throughout the City, and specifically the proposed Cool Route running east-west from Aldgate to London Wall. As summers become increasingly hot in a changing climate, it is important to provide routes that remain pleasant even in hot weather. These serve to mitigate heat stress, increase liveability and generally serve to encourage active travel. Within the project site, shade created from the surrounding buildings serves to lower ambient temperatures. With the addition of tree and understorey planting, this helps to create a more pleasant microclimate.

The 63 St Mary Axe tower’s ambition is to increase biodiversity in the City of London and to provide opportunities for biophilia. Biophilia translates as a “love of life”, where trees and plants on the ground and at every level flourish alongside humans and the built form. Providing for the human need to connect with nature, it is hoped that the planted tower will support good mental health and well-being.

download a project sheet

Camomile Street Public Realm © Fletcher Priest Architects

Houndsditch Street © Fletcher Priest Architects

Multi-function space © Fletcher Priest Architects

Camomile Park © Fletcher Priest Architects

back to projects