Carbon Definitions for the Built Environment, Buildings & Infrastructure
There remains significant inconsistency with respect to the basic definitions in use with reference to carbon and net zero carbon terminologies over the life cycle of buildings and infrastructure. This document provides a common set of definitions for the built environment sector. It has been put together initially by a working group within the Whole Life Carbon Network (WLCN, a group of some 90 built environment professionals) and including detailed discussions between WLCN, LETI, CIBSE, RIBA, RICS, IStructE, ICE, and UKGBC. The ‘Definitions’ are structured around CEN TC 350 life cycle modules, (e.g. BS EN 15978:2011 for buildings, BS EN 17472: 2022, PAS 2080:2016 for Infrastructure, BS EN 15643 2021.)
There are currently many variations in the terminology used to define carbon emissions (operational, embodied, whole life etc.) which leads to confusion amongst stakeholders. The definitions in this document build on the work of others but have been altered and developed as a ‘family’ of definitions that work together, with the intention of achieving greater consistency across the built environment industry. The ‘net zero carbon’ definitions in the document are based on the ‘Paris Proof’ approach which dictates that the Built Environment Industry should only use the limited amount of carbon – including energy and material resources – apportioned to it, in order for the UK economy as a whole to reach net zero emissions by 2050 and ensure best efforts to limit global warming to 1.5 degrees Celsius, a trajectory supported by the Science Based Targets Initiative. This requires reducing global built environment emissions by 50% by 2030, required by reducing global built environment emissions as a priority measure, and a decreasing reliance on offsets over time to achieve a net zero carbon balance.
This document represent LETI’s understanding of how we need to be designing to meet our climate change targets in 2020. This guide will evolve over time reflecting change in carbon budgets, technologies and capability of industry. LETI is collaborative by nature and is very interested in your feedback:
‘2020 is the year of climate action. We urgently need clear and practical guides on how to deliver net zero carbon future now. The new LETI guides fulfil this aim and are a timely addition to the growing suite of guides. This is a must read for construction professionals’
Gary Clark Chair of RIBA Sustainable Futures Group, Principal HOK London Studio
'Hawkins\Brown are happy to have collaborated with LETI on the production of the Emergency Climate Design Guide. Ensuring the construction industry, as a collective, recognise and minimise their impact on the environment must be one of the key design drivers for the coming years. This will take a collaborative, multi-disciplinary approach, which is why we have backed this important initiative with our time and support.'
Roger Hawkins Founding Partner Hawkins\Brown
'It’s like the buses: you wait for a conduit to help the industry turn climate rhetoric into action, and two come along at once. LETI’s Climate Emergency Design Guide and Embodied Carbon Primer are easy to use, well put together, effective tools that that remove any remaining excuses for not to getting on with it.'
Sunand Prasad Principal at Penoyre & Prasad
This document represent LETI’s understanding of how we need to be designing to meet our climate change targets in 2020. This guide will evolve over time reflecting change in carbon budgets, technologies and capability of industry. LETI is collaborative by nature and is very interested in your feedback.
Below is a general feedback form on the Embodied Carbon Primer:
In addition, the below survey has specific and more detailed questions on embodied carbon targets: