Most decarbonization efforts across the real estate industry have been centered on operational carbon—understandably so, given that 28 percent of global emissions come from building use.
Private and public investment has been focused on energy efficiency measures, on-site renewables and “greening” of the energy grids. Although there is still a way to go, the sector’s approach to tracking and reducing operational carbon is fairly well-established.
However, in-use emissions are just one part of the story. As buildings become more efficient and run on “cleaner” energy sources, the industry’s attention will need to include embodied carbon—emissions associated with the manufacturing and transportation of building materials, as well as the construction, maintenance and disposal of buildings.
Embodied carbon is currently responsible for 11 percent of global emissions and its share is likely to increase as buildings emit less during their operational lifetime. If the real estate industry is serious about achieving net zero by 2050, it must have a strategy to tackle whole lifecycle emissions. This is why at the annual C Change Summit last autumn, embodied carbon was the focus of the Future priorities for decarbonizing real estate session, where the audience had a chance to hear three different perspectives on the topic.
1. The importance of thoughtful design
Arjan Dingsté, Partner and Senior Architect at UNStudio, highlighted the importance of making thoughtful choices already at the early design stage of a development.
Adopting a whole lifecycle approach at the beginning of the process, and considering potential trade-offs associated with each decision made, can help maximize the total carbon reductions of a project. If embodied carbon is saved upfront, what will it mean for the operational emissions throughout a building’s lifetime? And conversely, if we prioritize operational efficiencies, what impact would it have on the upfront carbon required? Modelling whole life carbon during the design of a building can help answer these nuanced questions.
Some examples of those carefully weighed decisions, such us choosing insulation thickness for best thermal performance, deciding between double- and triple-glazing or optimizing window-to-wall ratios, are described in the Carbon Sweet Spot report, published by ULI last year.
UNStudio’s presentation also touched upon the costs associated with embodied carbon reductions. Although currently low-carbon developments can be more expensive – either due to higher prices or longer lead times of alternative materials – considered design and whole lifecycle modelling can already reduce embodied carbon by 50% without significant cost increases. Government initiatives, such as carbon taxation or financial incentives, could also help to tip the economical balance in the short term.
2. Asset owners and developers driving demand for low-carbon buildings
Clemens Brenninkmeijer, Head of Sustainability at Redevco B.V., addressed the role of embodied carbon emissions in achieving the firm’s Science Based Target of a ca. 50% reduction in absolute emissions by 2030, and to live up to the World GBC’s Net Zero Carbon Buildings Commitment.
A large part of the real estate asset manager’s activities include retrofit and development, and the presentation highlighted the key principles that the company follows to address embodied emissions resulting from its projects, emphasising that the greatest impact can be made at the earliest stages of the process.
Redevco prioritises retrofits and developing brownfield sites to avoid unnecessary embodied emissions in the first place. If that is not possible, each choice made at the design stage is evaluated against a whole lifecycle assessment and low-carbon, biobased materials are prioritised. The company also takes a long-term view and plans for the end-of-life of buildings by designing for disassembly or introducing material passports to effectively track and manage all components of a property. Offsetting is seen as the last resort and the quality of the offsets is carefully scrutinised.
These principles are also reflected in ULI’s Interactive Guide to Embodied Carbon – a user manual for real estate developers and owners which identifies key opportunities for embodied carbon reductions throughout all phases of the development process.
3. The role of low-carbon concrete
The final presentation, given by Dr. Andrew Minson, concrete and sustainable construction director at the Global Cement and Concrete Association (GCCA), centered around the need to decarbonize concrete—a material which is currently responsible for up to 8 percent of global emissions.
GCCA developed a global roadmap to net zero for the cement and concrete industry, estimating that 22 percent of emissions reductions can be achieved by increasing efficiency of the design and construction phases of developments, as well as through extending lifetime and encouraging the re-use of concrete components of buildings.
However, a considered approach to design and construction is not the only way in which the real estate sector can influence the emissions associated with concrete. Procurement policies which include low-carbon requirements can be a very effective tool for driving supply chain decarbonization, sending a clear demand signal to the manufacturers and incentivizing innovation. GCCA has published low-carbon and near-zero definitions/ratings that can be used by clients and project teams for low-carbon material procurement.
This approach can be also applied to other construction materials—read ULI’s Materials Movement report to learn how to integrate healthy, sustainable materials in development projects.
Value chain alignment can be the solution
This C Change summit presentation showcased three different perspectives on what role material manufacturers, architects and developers can play in tackling embodied emissions. Clearly, everyone can contribute to solving the issue: the industry needs low-carbon materials, efficient design and clear demand from clients. Decisions made at every stage of the development process have a tremendous impact on a building’s whole lifecycle emissions. However, it is also clear that to maximize the potential for embodied carbon reductions, collaboration across the entire value chain is essential – no one party can solve the challenge of embodied carbon in isolation.
Get involved!
If you have any questions or wish to find out more about how to get involved with C Change, please visit https://europe.uli.org/programmes/c-change/ or email [email protected].
C Change is a ULI-led programme to mobilise the European real estate industry to decarbonize. We’re a movement empowering everyone to work together for a sustainable future. We connect the brightest minds from across the value chain. We challenge barriers, share expertise, and champion innovation to move swiftly to accelerate solutions that will transform our industry and protect our planet. C Change means real change. C Change was formed in late 2021 by a group of leading real estate players that was united in its aim to focus on collaboration to ensure companies large and small have access to practical solutions and education on decarbonization.
