Embodied carbon refers to the carbon emitted during the production and use of construction materials. Around 1 in 10 tonnes of the UK’s total greenhouse gas emissions are classed as embodied carbon, and they total 64 million tonnes of CO2e per year – which is more than the UK’s aviation and shipping emissions combined.
Despite these concerning figures, embodied carbon emissions are unregulated in the UK. This has led to a mass call from the industry for legislation to be put into place to implement a standard way of calculating and reducing these emissions.
What is the Importance of An Embodied Carbon Assessment?
An embodied carbon assessment measures how many greenhouse gases are released through the supply chain of a material – from production to use. This includes material extraction, transport, refining, processing, assembly, use, and end-of-life. All these stages must be considered to gain an accurate understanding of a project’s carbon footprint.
Without carrying out an embodied carbon assessment during the production and use of construction materials, a large proportion of a building’s carbon emissions are ignored and so its true environmental impact cannot be ascertained. This can invalidate environmental credentials and risk possible future carbon costs.
How Do You Track Embodied Carbon?
Findings from embodied carbon assessments are key to informing future best practices for similar construction projects, influencing more sustainable design, procurement, construction, and disposal processes.
To measure the carbon emitted during the full lifecycle of a building, a Life-cycle Assessment (LCA) is required. This involves using various approved reference sources to define:
- Raw material extraction, transport, and manufacture
- The construction process and the building in use
- The emissions associated with demolition and potential reuse / recycling
What’s the Difference Between Embodied Carbon & Operational Carbon?
As we’ve seen, embodied carbon is the emissions produced by materials throughout the supply chain – from extraction, processing, and manufacture to construction, use, and disposal.
Operational carbon, on the other hand, is emitted during the occupancy of buildings. The emissions are produced when energy is used by heating, cooling, or lighting the building. This is typically assessed for Part L of the Building Regulations (Conservation of Fuel and Power).
How to Reduce Embodied Carbon
Industry leads are currently backing proposals for legal limits on embodied carbon, which would see an amendment to Part Z of the Building Regulations. This is likely to enforce mandatory limits for upfront carbon emissions on all building projects over 1,000 square metres from 2026, and mandatory assessments and reports on whole-life carbon on all residential and non-residential projects over 1,000 square metres from 2025.
The primary method for reducing embodied carbon is by using more resilient materials that will last longer and are produced via a more efficient construction process. Other methods include:
- Reusing buildings – with renovations saving between 50-75% of embodied carbon emissions when compared to constructing a new building.
- Using low-carbon concrete mixes – which are often easy to develop.
- Using less carbon-intensive materials – such as substituting plastic and foam insulation with straw and hemp.
- Reusing materials – with brand new steel having a carbon footprint 5 times greater than recycled content steel.
- Using fewer finishings – by considering alternatives to carpet or vinyl, or by leaving ceilings unfinished.
Other key concerns such as transportation can also often be forgotten and must be a key consideration during the design and procurement stage.
Whole Life & Embodied Carbon Assessments by Stroma
Stroma has long experience in delivering LCA and LCC assessments. Please get in touch to speak to us about our wide range of lifecycle analysis services, including for BREEAM, The Greater London Authority (GLA), or general planning requirements.