Measurement and reporting of embodied carbon in the construction industry

Tom Tang, a CIBSE Low Carbon Consultant, was part of the UK Green Building Council’s Advancing Net Zero team that explored the critical issue of embodied carbon within the construction and refurbishment of buildings. He shares the insights and findings of their report.

Embodied carbon constitutes 20% of the UK's built environment emissions. It encapsulates emissions associated with materials and construction processes throughout the lifecycle of a building or infrastructure. This includes processes, materials, and products used for construction, maintenance, repair, refurbishment, and end-of-life.

While some leading developers and organizations including AtkinsRéalis are actively measuring and optimizing embodied carbon footprints, mainstream adoption of such practices remains elusive. To address the environmental challenge posed by embodied carbon, it is imperative that we instill industry-wide consistency in embodied carbon modelling, enhance transparency in the modelling and reporting process, and foster responsible regulatory frameworks.

Working as part of the UK Green Building Council’s Advancing Net Zero team, Tom Tang helped create Embodied Carbon Modelling and Reporting. The guidance is aimed at practitioners, particularly those new to practice, with the goal of promoting rigorous and reliable reporting as the gold standard practice across the industry. UKGBC is an active affiliate of the World Green Building Council, and it is hoped that the same principles and practices will be adopted globally.

Creating best practice

We collaborated with 70+ professionals to review existing standards to identify areas for improvement; a smaller group undertook embodied carbon assessments for a real-life project across concept and technical design stages.

Building upon learning and results from recent academic studies that compared embodied carbon modelling tool performances, the document provides recommendations to enhance the quality and consistency of embodied carbon calculations, including conceptual proofs, immediately implementable suggestions, and requests for modeling tool developers.

Drawing from our experiences in delivering whole life carbon assessments across diverse sectors, we contributed to embodied carbon best practices and guidance in the document which reflects our commitment to informed and sustainable decision-making. Additionally, our involvement in the forthcoming UK Net Zero Carbon Building Standards, particularly within the embodied carbon task group, demonstrates our alignment with evolving industry best practices.

The UKGBC modelling and reporting guidance document encompasses key chapters including understanding and using Life Cycle Assessments and Environmental Product Declarations, comprehending default assumptions within the RICS Whole Life Carbon Assessment Professional Standard, establishing a Quality Assurance process for embodied carbon assessments, and providing guidance on the development and changes in embodied carbon assessments across RIBA stages.

Progress towards net zero goals

Despite being a significant source of carbon emissions, they are unregulated in the construction sector. The accurate measurement and reporting of embodied carbon are crucial for meaningful progress towards net zero carbon goals. This report aims to drive understanding, consistency, and reliability in embodied carbon assessments, addressing challenges, such as lack of standardization, transparency, and misrepresentation of sustainability performance.

The report is being pushed as a catalyst for driving understanding, consistency, and reliability in embodied carbon assessments, aiming to promote the transition from being a challenge addressed by leading organizations to one tackled collectively across the built environment industry. By providing valuable insights within the modelling process, clarity on typical assumptions made during the modelling process, and recommendations for creating transparency within assessments and reports, it advocates for a shift in perspective, positioning embodied carbon assessments not merely as accounting tools but as design means crucial for driving down whole life carbon.

This comprehensive effort signifies a step towards fostering a collective commitment to addressing the environmental impact of embodied carbon in the construction industry and engineering a better future for our planet and its people.

For more information download UKGBC’s Embodied Carbon Modelling and Reporting.