20 décembre 2021
Under Construction - Q4 2021 – 3 de 4 Publications
COP26 highlighted the complexity and challenges of decarbonisation and the transition towards net-zero. The Global Status Report for Buildings and Construction 2021 shows that the building and construction sector accounted for 36% of global final energy consumption and 37% of energy related CO2 emissions, as compared to other end use sectors.
Carbon emissions arising from the built environment are attributable not only to the use of built assets but also to their construction, from producing, procuring and transporting the materials and components used in the construction process to the emissions from maintenance, repair or replacement, and demolition and disposal.
To date, regulation in the UK has tended to focus on operational emissions from buildings but has not yet extended to the regulation and measurement of embodied carbon. In this context, the publication by the UKGBC, Net Zero Whole Life Carbon Roadmap for the Built Environment (Roadmap) which calls for mandatory measurement and reporting of whole life carbon marks a step towards possible regulation. Mandatory whole lifecycle carbon assessments for all new build and refurbishment projects are also called for by seventeen contractors and consultants in a letter to the Construction Minister on 7 December 2021.
According to the Roadmap, embodied carbon from the construction and refurbishment of buildings, which currently makes up 20% of built environment emissions, is likely to form over half the built environment emissions by 2035 as operational emissions start to decrease due to continued energy efficiency improvements, for example, due to tightening of requirements in Building Regulations (Part L) and EPC certificates. The use of voluntary sustainability assessment standards, such as BREEAM, and the planning system will also play their part in helping reduce carbon intensity. The Construction Playbook (p 5) urges contracting authorities to adopt the use of whole life carbon assessments to understand and minimise emissions from projects throughout their life-cycle and this is reflected in the London Plan 2021 which calls for whole-life cycle emission assessments for specific projects.
In terms of statutory pressure to measure embodied carbon, the Government’s Net Zero Strategy showed intent to "improve reporting on embodied carbon in buildings and infrastructure with a view to exploring a maximum level for new builds in the future" but stopped short of any planned regulation and measurement of embodied carbon.
By contrast, the publication of the Roadmap calls for the introduction of mandatory measurement and reporting of whole life carbon for large buildings to start as early as 2023. The Roadmap, created in conjunction with over 100 organisations from industry builds on the work of other industry initiatives showing what is needed to achieve net zero. This includes the suggested amendment to Part Z of the Building Regulations which outline the requirements for the assessment of whole life carbon emissions and the limitation of embodied carbon emissions for major projects.
If mandatory measurement is adopted, then consistency in methodology and reporting would also be needed so that the required data could be captured consistently. In this respect the industry is ahead of government since several initiatives and tools are available. These include the new International Cost Management Standard which proposes a toolkit for calculating and reporting the amount of generated or embodied carbon created in projects and the Built Environment Carbon Database, developed by a consortium of professional bodies, which aims to facilitate the recording of data to show how much carbon has been emitted during the manufacturing and construction process, along with future maintenance, energy use and demolition. These initiatives and the Roadmap build on numerous other construction industry guidance aimed at driving carbon improvements.
The Roadmap also calls for further action in addition to the regulation of embodied carbon for new buildings or major refurbishments, such as support for the decarbonisation of construction material supply chains, and other fiscal incentives, such as VAT reductions for refurbishment, to encourage re-use ahead of re-build. Additional recommended actions outlined are for developers to use embodied carbon targets and provisions requiring materials re-use in future projects, for designers to propose net zero designs and a design for performance approach, and for contractors to embark on work with their supply chains to reduce carbon emissions.
It’s clear that there will be a renewed focus on the need to measure and regulate embodied carbon in the coming years. However, what is less clear is when we are likely to see any such regulation. As data and technologies to measure embodied carbons increasingly become available, legislation would provide regulatory certainty as to what is required.
par Rona Westgate
par Emma Coates