Last edited 05 Sep 2017

Legislative Change Raises the Embodied Carbon Issue

The EU Environmental Impact Assessment (EIA) Directive (85/337/EEC) first came into force in 1985 and was transposed in UK legislation in 1988. Over the past nearly 30 years, the EIA regulations have provided local planning authorities and the planning inspectorate with a framework to facilitate the consideration of the likely environmental effects of a proposed development when granting planning permission. It also enables key stakeholders and the wider community to be given an opportunity to participate in the decision making process.

Although EIAs have been a force for good to limit damage to the environment; the fact that mitigation measures[1] are devised only if adverse significant environmental effects[2] have been identified is quite limiting. The very way significance is derived as a correlation between impact magnitude[3] against baseline conditions and receptor sensitivity[4] means that if the existing site is of low environmental value, it is less likely that there will be any significant environment effects to be mitigated against.

This is unfortunate. If during the habitat surveys, no protected species are identified, or a site is deemed of low ecological interest, it is unlikely significant effects will be identified. Nevertheless, shouldn’t the developer strive to enhance biodiversity by incorporating bird and bat boxes in the project, or devising a landscape strategy that favours local species to attract pollinators?

Due to the perceived rigid format of the EIA process, which is often considered a dull tick box exercise to comply with, rather than a vehicle to identify opportunities and drive sustainability on a project, EIA practitioners rarely detail enhancement opportunities as part of their environment statement (ES). Primarily because they are not legally required to (and thus, the client is not legally required to pay for it). Secondly, because of a lack of time in the programme to either foster meaningful engagement with the design team or to simply get the prerequisite information to explore opportunities before the planning submission.

Hopefully recent changes in legislation that came into force on 16th May 2017 to introduce the requirements of taking into consideration human health, land take and climate change as part of the EIA may help us reconsider how we approach setting baselines, devising significance and early engagement with the design team.

The changes require the climate change section of the EIA to tackle adaptation and greenhouse gas emissions. Although minimising operational carbon throughout the design is already well established, the EIA requirement will provide an additional driver alongside Part L and local planning authorities’ specific targets to reduce CO2e emissions.

A legal requirement to consider and minimise embodied carbon however is new. Furthermore, as detailed in the IEMA guidance on Assessing Greenhouse Gas (GHG) Emissions and Evaluating their Significance, it is anticipated that any level of GHG emissions produced as a result of a development are likely to trigger ‘significant effects’. The guidance indicates that: “the GHG emissions from all projects will contribute to climate change; the largest interrelated cumulative environmental effect” and “the consequences of a changing climate have the potential to lead to significant environmental effects on all topics in the EIA Directive.”

This means not only will embodied carbon assessment become a standard feature of the EIA and early design, but a detailed list of mitigation measures demonstrating how the design has been influenced as a result of early assessment will be expected from local planning authorities. While the new legislation does not provide guidance as to the methodology for assessing embodied carbon, KLH Sustainability have developed a number of bespoke tools to be able to do that analysis iteratively over the full design process.

So, developers and design teams: make sure carbon becomes a decision factor alongside cost and programme to be able to robustly demonstrate as part of the planning process how this influenced your proposed development’s proposal. From our experience, it is important to engage early in design to model embodied carbon to be able to influence changes in the design that will truly mitigate those carbon impacts.



[1] Mitigation measures: actions to reduce adverse (negative) environmental effects

[2] Effect: the consequence of an impact while the impact is defined as the change against the baseline

[3] Impact magnitude: the extent of the change, how severe it is.

[4] Receptor sensitivity (or value): how valuable or sensitive/fragile/delicate a receptor is - be an ecosystem or people.