The Entopia Building, Cambridge

2025 RIBA East Award
2025 RIBA East Project Architect of the Year Mark Martines
2025 RIBA East Sustainability Award sponsored by Autodesk

Offices
Architype, Feilden and Mawson and Eve Waldron Design for The University of Cambridge
Contract value: £10.54m
GIA: 2,939m²
Cost per m²: £3,586

Buildings carry the potential to serve as experimental test beds. In the case of Entopia, this is achieved through the clever reuse of a disused 1930s Cambridge telephone exchange, which itself had been partially altered during the 1990s. 

Architype’s design demonstrates how far one can go in terms of retrofitting, not least due to its firm and principled decision to retain every one of the building’s usable existing features – even those they would have otherwise chosen to redesign. 

A clear objective throughout was therefore to minimise the amount of additional carbon emissions that would be created by the refurbishment process. To that end, many of the light fittings were salvaged from a London café, and the main entrance desk was repurposed from one which had previously sat in Netflix’s UK headquarters. All in all, it creates an eclectic aesthetic which the architects clearly revelled in.

In terms of operational carbon, the Entopia building is outstanding. The solid exterior walls are insulated internally with ‘breathing wall’ bio-based materials. New high-performance windows were installed even though, if considered from a conservation standpoint, they look incongruous when compared to the original interwar sash windows. 

Energy use is astonishingly low. Acoustic surfaces and triple glazing mean that any noise from the buses and cars on the street outside is totally silenced. Altogether, the scheme asks us to choose what we really want when it comes to retrofitting a building: a coherent new aesthetic appearance, or the best possible environmental principles and performance?

Cambridge University regards Entopia as its standard-bearer for a more sustainable estates policy. The building is being used for some university teaching but otherwise is primarily focused on interdisciplinary environmental research projects. 

To the rear are start-up facilities which are on offer to any new companies that are pursuing sustainability goals, and this includes a few small architectural practices. This admirable combination of programme and performance manages to ensure that a genuinely high standard of environmental principles permeates its design throughout.

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RIBA UK Awards 2025 sponsored by Autodesk, EH Smith, Equitone and VELUX