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Cambridge Institute for Sustainability Leadership (CISL)


5 May 2021 – Tim Forman, Course Director for the Sustainability Leadership for the Built Environment (IDBE) Master’s and Postgraduate Certificate, discusses the need for a radical shift in thinking and in preparedness to invest in the energy efficiency of buildings and built environments in order to achieve real impact.

While growing numbers of organisations, including over a fifth of the world’s largest companies, are responding to the climate and environment emergencies and forging new paths to a decarbonised future, the built environment sector is lagging behind in addressing the energy inefficiency of our buildings, towns and cities.

This is brought into sharp focus when you consider the impacts the construction and operation of our built environments have. Together they account for roughly one-third of global energy consumption and almost 40% of total direct and indirect CO2 emissions. Decarbonising the built environment sector as a whole by 2050 requires emissions cuts of roughly 6% annually. Yet the sector’s demand for energy continues to rise and sectoral emissions today are 25% higher than they were in 2000.

The UK has about 28 million homes, which, by most assessments, constitute the oldest and least energy efficient national housing stock in Europe. Decarbonising our housing and making all homes affordable, safe and healthy is a massive challenge: to improve 80% of our nation’s homes by 2050, we will need to treat one home every 40 seconds - assuming we only do this once for each home. This calls for a radical shift in our thinking and our preparedness to invest in the energy efficiency of our buildings and built environments. 

This is a stark challenge, but it is also a once-in-a-generation opportunity to invest in efficiency gains. Investment will recoup otherwise lost expenditure, improve societal resilience, create new economic activity and innovation, and measurably improve health and wellbeing as a result of better housing. 

The ‘green jobs’ created by increasing demand for retrofit have the potential to create enduring social value through growth in skills, knowledge and employment opportunities. This potential for job creation is enormous: it was recently estimated that if the Government and National Infrastructure Bank supported a wide scale programme of retrofitting, 200,000 jobs could be created by 2030.

Decarbonising a building requires investment, fine-tuning and thoughtful operation and maintenance. The cost and complexity of retrofitting,  particularly ‘deep retrofitting’, to achieve low or zero operational carbon emissions, are challenges vast enough to fuel a ‘space race’ of innovation and development in the building sector. Deep retrofitting requires buildings to be treated as complex systems, in which energy, air and moisture flows are managed together to reduce carbon intensity - we need to develop industry’s capacity to do this cheaply and effectively. 

Investment in retrofit programmes will catalyse economic activity and growth of sustainable value chains and will ultimately drive improvement in technology and reduction in cost per building. Individual building owners and occupiers cannot achieve sector-wide decarbonisation without the coordination of government, finance and industry, so we need public investment and aligned incentives in housing improvement at a national scale. We also need the private sector to collectively mobilise to invest, commission and drive pro-active change on this agenda.

Sensible strategies will take advantage of scale (for instance, by retrofitting hundreds of homes in a neighbourhood at once), draw on interdisciplinary coordination from across sectors, establish public trust and buy-in, incentivise stable investment and the sharing of risk and develop long-term skilled employment. To achieve our national retrofit imperative, we need much more than the right technology. 

Societies across the world have a generation’s worth of work to do decarbonising their existing built environments. Forward-looking organisations in industry are looking for business opportunities in our ‘no-build/low-build’ future.

At CISL, we are seizing the opportunity to retrofit our new headquarters, the Entopia Building (built in the 1930’s to house the Cambridge Telephone Exchange), to reduce its ‘whole life’ impacts and create shared social value. The building, which will also provide space to regional organisations, will become the UK’s largest office refurbished to a passive energy standard (EnerPHit) and the first to combine EnerPHit, BREEAM Outstanding and WELL standards for sustainability, health and wellbeing. Its design and fit-out are following circular economy principles, and we are achieving all of this through a collaborative and innovative project approach, which will ensure social value is shared locally and across the sector. 

The transition to a sustainable economy requires us to rethink, innovate, and find new ways of doing business. Now is the time for action.

Would you like to gain a deeper understanding of the challenges and opportunities facing the built environment? The part-time time Sustainability Leadership for the Built Environment (IDBE) Master’s and Postgraduate Certificate explore the importance of building knowledge and leadership skills to drive real change through multiple professions and disciplines working together. Find out more and download a course brochure.

About the author

Tim Forman is Senior Research Associate and Course Director for the Sustainability Leadership for the Built Environment (IDBE) postgraduate programme.


Articles on the blog written by employees of the University of Cambridge Institute for Sustainability Leadership (CISL) do not necessarily represent the views of, or endorsement by, the Institute or the wider University of Cambridge.


Zoe Kalus, Head of Media  

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