Stone Demonstrator

A full-scale prototype built from pre-tensioned stone that challenges how modern buildings are made. Standing three storeys tall at Empress Place, the Stone Demonstrator tests stone’s potential as a low-carbon structural material.

Client

Design Museum
Architect

Groupwork
Photography

Bas Princen
Stone Mason

The Stonemasonry Company
Main Contractor

Ernest Park
Partners

The Earls Court Development Company, The UKRI Arts and Humanities Research Council
Completion

2025

The public installation, designed with Groupwork, sits on the Earls Court development site in west London and shows how stone could take the place of steel and concrete as a primary structural material. Backed by Future Observatory and the UKRI Arts and Humanities Research Council, the project works as both a research tool and a public statement about more sustainable construction.

Nearly 40% of global carbon emissions come from the built environment, with about 11% tied to constructing new buildings. Natural stone offers a route to cut this sharply. Compared with a conventional reinforced concrete frame, the Stone Demonstrator drops embodied carbon by roughly 70%, and by around 90% when set against steel.

The structure rises three storeys, measuring 6.5 by 6.5 metres, and is assembled from stone blocks threaded with steel tendons and compressed to form pre-tensioned beams and columns. The floorplates use a mix of systems: pre-tensioned stone slabs that follow the logic of the frame, dowel-laminated timber slabs, and a hybrid stone and glulam option invented by Webb Yates that fixes thin stone to glulam to create a lighter, low-carbon composite panel. The roof is dowel-laminated timber. The stone brick façade is self-supporting and uses blocks with around 90% lower emissions than standard fired clay bricks.

The project forms part of a wider push by Future Observatory and the AHRC to support sustainable design research, funding more than a hundred projects so far. In parallel, research led by Professor Wendel Sebastian at UCL is developing a practical design guide for stone structures to help move stone construction into everyday use and prepare for future building codes.

This structural approach has been developed for buildings up to 80 storeys in seismic regions of the Mediterranean, 30 storeys at Canary Wharf, and 35 storeys for a residential scheme in Bristol. The self-supporting stone façades, built to standard brick dimensions, can rise six storeys without bearing on the primary frame and only need light restraint. For taller schemes, the system adapts, combining timber superstructures with stone or metal framing to meet fire and safety requirements.

The Stone Demonstrator sits within a wider push by Future Observatory and the AHRC to support sustainable design research, funding more than a hundred projects to date. The project runs alongside research led by Professor Wendel Sebastian at UCL, developing a practical design guide for stone structures. This work aims to make stone construction easier to adopt and lays the groundwork for future building codes.

The Earls Court site, one of central London’s major regeneration areas, will become a new mixed-use neighbourhood of housing, workspaces and cultural venues. Its proximity to the Design Museum makes it an ideal setting to demonstrate the potential of low-carbon stone structures and to engage the wider construction industry.

This structural system has been developed for buildings up to 80 storeys in seismic regions of the Mediterranean, 30 storeys at Canary Wharf, and 35 storeys for a residential scheme in Bristol. The self-supporting stone façades, built to standard brick dimensions, can stand six storeys without loading the structural frame, needing only light restraint from wind posts. In taller buildings, the approach adapts, combining timber superstructures with stone or metal framing to meet fire and safety regulations.

With thanks to the project partners and suppliers:

Hutton Stone
Albion Stone
Bamberger Natursteinwerk Hermann Graser
Arup
Ryker Structures
Bishop Facades
IQ Wood
Brachot
Carrière de Luget
Franken-Schotter
Lundhs
SigmaRoc
Rossmore Contracts