Xavier Le Den
March 30, 2022
Embodied carbon and how to tackle it
Even before the first occupant of a new building steps inside the building vast amounts of CO2 has been produced. Carbon emitted during the construction of buildings and infrastructure connected to materials, transportation, and installation are called embodied carbon and amounts to 10% of global co2 emissions. A new report offers ways to mitigate these emissions.
A new study, 'Towards embodied carbon benchmarks for buildings in Europe', by Ramboll, in collaboration with leading researchers from Aalborg University Build and KU Leuven sets out a framework for benchmarking and limiting the embodied carbon of new buildings.
Reducing embodied carbon to levels aligned with the Paris Agreement requires carbon budgets for buildings linked to national emissions reduction targets. The study shows that this kind of consideration is not yet sufficiently developed in existing initiatives.
Critically, it proposes a new methodology to define and implement Paris-aligned budgets and pathways related to reduction of embodied carbon in buildings.
“Current voluntary efforts, including certification schemes, and existing European legislation fall short of setting granular targets, based on robust data, which are necessary to reduce embodied carbon in line with the Paris Agreement” Says, Harpa Birgisdottir, Research Group Leader for BUILD at Aalborg University
The Study identifies solutions to measure embodied carbon, define carbon budgets and targets. Importantly it includes recommendations for a baseline of current embodied carbon levels in new buildings, as well as considerations of the available carbon budget for these emissions. This will form the basis of a performance system in the shape of benchmarks for the reduction of embodied carbon.
On average 600 t CO2e embodied carbon is emitted for a newly constructed building of 1000 m2 throughout its lifecycle. Urbanisation and population growth has driven the construction of new buildings to an all-time high, basically implying that the buildings and construction sector is standing in the way of us delivering on our Paris agreement commitments of limiting global warming to well below 2°C.
“We should be working towards buildings that are around 300 t CO2e embodied carbon. For the sector to meet such ambitious targets we need a framework relating to carbon budgets, and to benchmark embodied carbon in the built environment.” says, Lars Riemann, Executive Director Ramboll Buildings.
Embodied carbon has long been a hidden part in the climate impact of a building, as many climate policies and reduction initiatives focus on the operational emissions related to the use of the building.
The study gathers data from multiple sources and explores case studies in five European countries, the conclusions are shows that embodied carbon various greatly depending on the building type, structure, and materials used.
Download the reports here:
> 3. Defining budget-based targets. A top-down approach > 4. Bridging the embodied carbon performance gap > All 4 reports in 1 - get it all in one file > Summary report - The important takeaways in short
The study focuses on the European Union (EU), which is pioneering built environment greenhouse gas-emission reduction policies via instruments such as the Energy Performance of Buildings Directive, the Taxonomy for Sustainable Activities, and the EU Climate Transition Benchmark Regulation.
These instruments and initiatives have increased awareness of the need for the real estate sector to consider, measure and consequently reduce embodied carbon, as part of a ‘whole lifecycle’ approach.
However, there is a need for the industry to step up. The new study shows that current efforts fall short. James Drinkwater, Head of Built Environment at Laudes Foundation says:
“This study shows how policy-makers can start to set carbon budgets, spark industry innovation to meet these targets, and significantly reduce emissions this decade.”
Effective measures to reduce the embodied carbon of buildings require robust data on the current levels of such emissions from different life cycle stages, building types, building elements and materials. The study shows that large samples of such data are critically missing, and existing datasets faces a series of challenges if they are to be useful for robust embodied carbon benchmarks.
Key recommendations in the study are for policymakers to define and promote standardised and centralised data collection methods for emissions life cycle assessments (LCA). Furthermore, it’s evident that there is a need for certification bodies to require LCAs for all new buildings and ensuring that available data is shared.
Investors can help drive down embodied emissions by requiring LCAs for all new buildings and align their portfolios with identified benchmarks if they wish to be Paris agreement aligned and thereby also anticipate any regulatory risks. Sharing knowledge and approaches is essential and buildings designers must design with these benchmarks in mind, advocating low-carbon solutions. To learn more about the study and download the reports from the study, go to our "Embodied Carbon in the Building Sector website"