In response to the latest Draft London Plan Policy, eTool takes a closer look at the importance of Whole Life-Cycle Carbon Assessments (WLC) and the latest guidance.
Draft London Plan Policy SI 2 sets out a requirement for developments to calculate and reduce WLC emissions. This requirement applies to planning applications which are referred to the Mayor, but WLC assessments are encouraged for all major applications. Guidance has been published to explain how the assessment of these carbon emissions should be approached and presented, and all planning applications referred to the Mayor must include a WLC assessment prepared in accordance with the WLC guidance document.(¹)
National Building Regulations and the Mayor’s net zero-carbon target for new development currently only account for a building’s operational carbon emissions. As methods and approaches for reducing operational emissions have become better understood, and as targets have become more stringent, these emissions are now beginning to make up a declining proportion of a development’s WLC emissions. Attention now needs to turn to WLC to incorporate the embodied emissions of a development.(2)
Whole Life-Cycle Carbon (WLC) emissions are the carbon emissions resulting from the materials, construction and the use of a building over its entire life, including its demolition and disposal. It is widely accepted that a WLC assessment provides a true picture of a building’s carbon impact on the environment.
Applicants should use benchmarks figures provided as a guide for the design team. Projects with higher emissions should discuss design improvements to reduce emissions early in the concept stage. Aspirational targets are encouraged in line with the World Green Building Council reduction of 40% embodied carbon emissions by 2030.
eTool makes the Office Benchmark model available online for all eToolLCD users, including Open Users, to encourage design teams to engage LCA early in the design process. eTool Benchmark figures are closely aligned with the Policy Benchmarks as detailed below.
Click here to create an account and check the model online for more details. eToolLCD Benchmark model available online includes all modules.
What methodology should be used?
WLC assessments should be carried out using a nationally recognised assessment methodology.
In the UK, the recognised framework for appraising environmental impacts of the built environment is BS EN 15978. This standard was adopted for use by eTool since its release in 2011 (this article expands on EN 15978 further: https://etoolglobal.com/eblog/environment/en-15978/ ).
Supporting the BS EN 15978 is the now widely used RICS Professional Statement: Whole Life Carbon assessment for the built environment(3). It is this RICS policy that should be used as the methodology for assessment when developing a WLC assessment for compliance with Draft London Plan Policy SI 2 (this article explains how eToolLCD adheres to the RICS Professional Statement: Whole Life Carbon assessment https://support.etoollcd.com/index.php/knowledgebase/etoollcd-and-rics-whole-of-life-carbon-assessment-for-the-built-environment/ )
Both BS EN 15978 and the RICS Professional Statement: Whole Life Carbon assessment for the built environment, set out four stages in the life of a typical project and It effectively defines the goal, scope and method of the system boundary.
A WLC assessment should cover the entirety of modules A, B, C and D to comply with the London Plan Policy SI 2, with a reference study period (assumed life expectancy of a building) of 60 years.
What about materials and products?
With regards to acceptable sources of carbon data for materials and products, there is an emphasis on EPD’s and equivalent datasets in accordance with EN 15804, ISO 21930, ISO 14067, ISO 14025, ISO 14040/14044 and PAS 2050.
When it comes to biogenic carbon from the use of timber, this should be assessed in accordance with Clause 3.4.1 of the RICS Professional Statement: Whole Life Carbon assessment for the built environment, and included within the reported totals for modules A1-A3.
Figures should be based on the current status of the electricity grid, in order to provide a point in time assessment, however it is also important to consider the possible long term decarbonisation of the grid and how it could impact design decisions. Therefore, a second set of figures should be provided based on the expected decarbonisation of the electricity grid over the lifetime of the development (i.e. 60 years). This should be done in accordance with the ‘National Grid’s Future Energy Scenario: Slow progression’, including in relation to the EPDs of all materials (UK and non-UK, for simplicity)(4)
eTool will continue to work with UK Industry Bodies and working groups to offer our ongoing support on the above subject and guidance relating to Life Cycle Design.