Building Entopia
This is not an ordinary project
“This is not an ordinary project,” proclaimed the hoarding, “But it needs to be.”
If you’d strolled along Cambridge’s Regent Street during 2021 you would have spotted this intriguing proclamation, writ large across toughened board and fluttering sheeting.
Behind the bold black type something extraordinary was happening: a team was busy at work, transforming a 1930s telephone exchange into one of the world’s most sustainable retrofitted buildings, which is now the new home of the Cambridge Institute for Sustainability Leadership (CISL), and its new Canopy workspace.
CISL has been exploring ways to build more sustainable economies for over three decades, so sought to create an HQ that ‘walked the talk’ – that had the smallest possible carbon footprint, and that set new sustainability standards for the modern-day office.
The building sector, including the construction and operation of buildings, accounts for nearly a third of all energy consumed across the world. The sector produces nearly 15% of direct CO2 emissions.
A major challenge lies right on our doorstep: as much as 75% of European building stock is energy inefficient. The World Green Building Council has set an ambition for every building to be net zero by 2050 and is calling on governments and businesses world-wide to act.
The Entopia building is a rallying cry to encourage and inspire developers, businesses and occupiers to change the way they design and run buildings for the future.
Global share of buildings and construction final energy and emissions, 2019 The 2020 Global Status Report for Buildings and Construction, UNEP
Global share of buildings and construction final energy and emissions, 2019 The 2020 Global Status Report for Buildings and Construction, UNEP
“The path to a sustainable and resilient world will not be feasible without radical changes in the way we procure, design, construct and use our buildings. Through Entopia, we wanted to demonstrate that climate emergency challenges could be addressed meaningfully in a single building.”
Clare Shine, Director and CEO, CISL
The brief
The Entopia project aimed to show that retrofitting an existing building could be delivered at a cost competitive to a conventional office refurbishment and wanted to maximise:
Recycled and reclaimed materials
• The ‘inspiration’ factor for all staff and visitors
• Collaboration among staff
And minimise:
Negative impacts on the environment
• ‘Whole life embodied carbon’ – the amount of carbon emitted when sourcing, processing and installing materials as well as on-going running of the building
• Energy use
The question was, could CISL’s ambitious vision be realised through the refurbishment and retrofit of 1 Regent Street?
Sustainability targets were selected to focus performance and enshrined into the project charter.
BREEAM ‘outstanding’ – confirming high sustainability standards across the building’s entire lifetime including reduced energy consumption and waste, recycling and positive social impact
Passivhaus EnerPHit ‘classic’ standard – proving Entopia has hit targets for retrofitted buildings covering insulation and airtightness, energy use and ventilation
WELL ‘gold’ standard – confirming the building has high-quality elements such as natural light, comfort, air and water to improve the health and well-being of staff.
Building change
SOLK Photography Ltd/Architype
SOLK Photography Ltd/Architype
SOLK Photography Ltd/Architype
SOLK Photography Ltd/Architype
CISL pulled together a team of sustainability experts, architects, engineers and designer to rise to the ‘retrofit’ challenge.
The starting point was understanding the building and working within its limits. This approach, known as ‘fabric-first’, focused on improving the energy performance of the exterior and scaling down mechanical and electrical systems and plumbing as much as possible. This in turn would cut carbon emissions and costs, and free up space.
Recycling was central: the project team scoured local sources for second-hand materials rather than buying new wherever possible.
The philosophy behind the entire project was ‘whole-life design’. This meant that when making a design decision, the team explored the future impact across the entire lifetime of the building, taking into account long-term costs not just upfront investment. For example, installing triple glazing was a chunky investment, but it would pay off in the form of reduced energy bills over decades.
The Entopia Building, formerly 1 Regent Street, is a five-storey concrete frame structure with a basement originally constructed in 1939. The refurbishment and retrofit ran from 2021-2022 and is cost £12.67 million (pending final adjustments).
35% cut in heat loss
15% energy requirements of original building
62,332kg CO2e avoided in construction materials
SOLK Photography for ISG
SOLK Photography for ISG
21,000 kg of CO2e saved through reclaimed materials such as the PV rooftop canopy, lighting and furniture, fixtures and equipment.
Photo by SOLK Photography for ISG
Photo by SOLK Photography for ISG
48% bio-based materials incorporated by volume
77% increase in natural light
350 recycled LED lights
SOLK Photography for ISG
SOLK Photography for ISG
5,139 items/43,409kg diverted from landfill
£163,787 worth of kit donated to the community
85,747kg of CO2e avoided
SOLK Photography Ltd/Architype
SOLK Photography Ltd/Architype
Reception desk recycled from Netflix
Open for business
Entopia was opened on 31 March 2022 by HM King Charles III. It now provides approximately 3,000m2 of renovated space for CISL’s Cambridge-based staff and the Canopy workspace.
With a total construction cost of £317/ft2, Entopia demonstrates that a ‘deep green’ retrofit can be delivered at a cost that is competitive to a conventional office refurbishment (excluding replacement of external envelope) of between £200-£300/ft2.
“Entopia’s true impact is still to come through its role as a beacon project: an exemplar and teachable resource that creates positive ripples of change throughout the built environment community, influencing the course of other projects, policies and investments.”
The Entopia Communications Working Group
About CISL
CISL partners with business and governments around the world to develop leadership and solutions for a sustainable economy. Central to this mission is CISL's global community for action, with over 27,000 leaders and pioneers.
CISL’s Canopy workspace, also based within Entopia, provides the space, support and networks for small businesses and start-ups in sustainability to thrive and grow.
- Words by Lee's Stores
- Photography: SOLK Photography Ltd for Architype and ISG
- Video by Chris Loades
- Interior design renders by Eve Waldron Design
- Cutaway of the Entopia building provided by Feilden+Mawson.
SOLK Photography Ltd / Architype
SOLK Photography Ltd / Architype
Built with Shorthand