Menu
The built environment contributes to approximately 40% of global carbon emissions. It is therefore crucial that buildings monitor and reduce their associated emissions to ensure net zero carbon targets are met.
The key metrics in assessing carbon are ‘embodied carbon’ and ‘operational carbon’. Embodied carbon refers to the greenhouse gas (GHG) emissions from the manufacturing, transportation, installation, maintenance and disposal of building materials. Operational carbon is related to the emissions from a building’s energy and water use throughout its life. Collectively, these metrics cover ‘whole life carbon’ which is the sum total of all asset related GHG emissions and removals, both operational and embodied over the life cycle of an asset including its disposal.
To measure these emissions and their impact on climate change, sustainability experts carry out life cycle assessments (LCAs). LCAs track emissions throughout the entire life cycle of a product, process or building, and convert them into metrics that indicate their potential environmental impacts.
The most commonly used metric is global warming potential (GWP) which is measured in kilograms of carbon dioxide equivalent (kgCO2e).
The Royal Institution of Chartered Surveyors (RICS) have provided technical standards to facilitate accuracy in carrying out carbon assessment and ensure a consistent methodology is adopted. The RICS 2nd Edition of the ‘whole life carbon assessment for the built environment’ professional standard was published in September 2023 and became effective from 1st July 2024. It represents a significant advancement in carbon measurement in the built environment. The transition from the 1st to the 2nd edition signifies a more inclusive, comprehensive and globally harmonised approach to carbon assessment. This update addresses the industry’s immediate needs and positions the standard as a leading framework for achieving sustainability and net-zero goals across built and natural environments.
The 2nd edition expands its scope to include not only buildings but also infrastructure and all built assets, making it applicable internationally. This allows for consistent reporting across a broader range of asset types, engaging more surveyors and stakeholders in the built environment. The 2nd edition also now includes the inclusion of any on-site demolition or strip-out works required at the beginning of the project (reported under sub-module A5.1).
The 2nd edition introduces two pivotal guides to facilitate the understanding, endorsement and adoption of the Whole Life Carbon Assessment (WLCA) standard globally, addressing the need for a harmonised approach to whole life carbon assessments. The new guidance includes the latest industry-agreed definitions for carbon terminology, facilitating a clear understanding and standardised approach to assessing risk in carbon assessment reporting.
By highlighting the carbon cost of different design choices, the 2nd edition aligns with international sustainability pledges and provides tools for the industry to move towards decarbonisation. The focus on whole life carbon assessments underscores RICS’s commitment to leading the industry towards sustainable practices.
The 2nd edition aligns with the International Cost Management Standards (ICMS), ensuring greater consistency in construction costings globally and supporting compliance with government carbon reduction commitments and industry reporting requirements.
The new standard emphasises a consistent and comprehensive methodology for assessing emissions over an asset’s lifecycle. It is based on six key principles: comprehensive, data-driven, consistent, practical, aligned and integrated. This approach aims to manage carbon budgets, reduce lifetime emissions and support a net-zero future. Further information is detailed below.
The updated methodology detailed in the 2nd edition of the RICS professional standard includes the following key changes:
As the guidance evolves, so too does the carbon intensity of building materials. In the UK, the primary method for reducing the carbon intensity of concrete has previously been by using ground granulated blast furnace slag (GGBS) as a supplementary cementitious material (SCM) to replace traditional Portland cement. However, GGBS is a limited resource that is almost fully utilised globally. Any increase in its use in one location will simply result in a reduction of its use elsewhere thus failing to decrease global emissions. The latest guidance is that GGBS should therefore continue to be used only when required technically and where available locally – i.e. not purely for carbon saving purposes and it is expected that this will be reflected in a higher carbon intensity figure for GGBS in the near future.
In summary, there is a growing demand for carbon assessments and the importance of carbon and these types of assessment is increasing every day. Many of our clients have developed comprehensive ESG targets which include indicators such as carbon emissions and energy intensity targets in response to its importance in the industry as a whole. Manufacturers are also recognising the importance of these types of assessment with many manufacturers now offering an Environmental Product Declaration (EPD) or completed CIBSE TM65 assessment which provide information about the carbon intensity of a product.
The industry is rapidly evolving and the accuracy of carbon assessments will only improve as more information is available and more detailed data is provided. For more information, please contact our sustainability team.
