Former BT Headquarters to become London’s first net zero office development


THE CITY of London Planning & Transportation Committee has approved plans for a deep retrofit of 81 Newgate Street, the former BT Headquarters, to be the first net zero carbon-enabled office development in London.

It was designed by Kohn Pedersen Fox Associates (KPF) for Tejat V Lux Sàrl, advised by Orion Capital Managers and Pella Real Estate Partners.

The design will transform a 1980’s office block into a sustainable, mixed-use building that is embedded in the wider public life of the City as a new gateway destination into London’s ‘Culture Mile’.

KPF Design Principal John Bushell commented on the project: “81 Newgate Street develops a number of reuse and transformation themes that KPF has been working on for a long time, from the World Bank in Washington DC, completed in 1996, to more recent projects in London, such as Unilever House, South Bank Tower and a collection of projects in Covent Garden.

“The mixture of reuse and invention generates projects with great character, preserving history whilst allowing for vigorous renewal and making substantial savings of embodied carbon.”

The outdated 1980’s single-use office building has been reimagined by KPF through extension, refurbishment and modernisation.

The design enables the creation of large, flexible office floor plates, with increased daylight, improved internal experience and plentiful outside space, in a highly sustainable way.

The structural frame is substantially retained and extended with a net increase in commercial office space.

This is partially achieved by inserting new cores into the existing atrium void and refilling the remaining space.

Three new ‘slot atria’, rising the full height of the building and topped by skylights, announce main building entrances as well as defining the internal circulation space and the public route at ground floor level.

Internally, they frame key views of Christchurch Greyfriars Church Garden, St. Paul’s and the Eastern cluster.

On the roof, a large public terrace will be created, with a restaurant, wildflower meadow and feature access stairs, all providing a unique view of St. Paul’s Cathedral.

This garden is designed to feel part of the architectural language of the building, but the primary experience is of a natural landscape setting for the City panorama.

The roof garden and large planters on accessible terraces, alongside areas of green wall, will make a significant contribution to the ‘greening’ of the City – contributing to local biodiversity and air quality improvements, as well as providing an enjoyable amenity.

A gym, swimming pool and spa facilities are included, in addition to long and short-term bicycle parking with associated facilities to promote sustainable transport.

Through reuse, the project will deliver the lowest impact form of development for the site – saving up to three years of demolition and new construction – and providing embodied carbon savings from reused material and modern construction processes.

The environmental performance of the building will be improved and environmental impact minimised by reusing Portland stone from the existing building, employing modular construction methods, specifying low carbon materials and adopting a zero to landfill policy.

Additionally, the development aims to be air quality neutral when completed, to provide one of the highest ‘urban greening factors’ in London.