What’s stopping us from regulating embodied carbon?

Over the last few years, the conversation around sustainable design in the construction industry has expanded massively and most companies are at least considering low carbon options in their designs, even if these ideas aren’t fully realised. And while there is regulation around operational energy use, the measurement and use of embodied carbon remains unregulated. Target values are still just targets, and most of those are relatively un-ambitious.

I think it’s fair to say that most engineers and architects are measuring the embodied carbon of their buildings in the same way, but there are inevitably parts of any building that don’t quite fit the boxes in the guidance documents. At that point a less prudent engineer or architect could include or exclude values to help to tell the story that their client wants, particularly as embodied carbon assessments are rarely checked or audited.

So how can we make sure the values we’re comparing have accounted for the same things? And more importantly, how can we make sure that everyone is working to reduce the carbon in their projects?

Regulating embodied carbon would certainly help and is something that the Architect’s Climate Action Network (ACAN) have been regularly campaigning for, including outside government. Among several suggestions, ACAN would like to see enforced limits on embodied carbon for all developments by 2025.

The proposed Part Z amendment to the Building Regulations would also make the measurement of embodied carbon compulsory, together with reduction targets over the coming years. With measurement more carefully controlled and audited, and embodied carbon limits set for every project, it would level the playing field and make sure that all developments were giving embodied carbon the consideration it needs.

In other cities around the world these kinds of regulations are already starting to be brought in; Copenhagen has well defined year on year reduction targets for embodied carbon and the city of Oslo has had a carbon budget since 2017. The city of Toronto has gone one step further and recently implemented regulation which requires new city-owned buildings to have an upfront embodied carbon of less than 350kgCO2e/m2, a target that is expected to be implemented for all buildings by 2025. Considerably more ambitious than the targets we’re setting in the UK.

The problem is that the only way that the regulation would work is if it’s enforced and that currently poses some difficulties. Materials with low embodied carbon are in high demand, and with finite amounts of cement replacement products or re-used steel available, it’s clear that not every project will be able to source the materials they’d need. We’d be setting a target without the resources available to achieve it.

And whilst the construction industry might be open to using different materials if they’re available, it hasn’t yet accepted that what we really need to do is build less. It’s possible we’d end up with a situation where developers would simply pay to offset their carbon instead.

But if necessity is the mother of invention, then as we try to move towards lower carbon construction perhaps this combination of increased regulation and a shortage of low carbon materials could actually help us to find more innovative design solutions. If a lower target makes it difficult to build using conventional materials, then maybe there will be more incentive to create new materials or find new ways of building that are meeting the targets. Maybe then we can start to accelerate these changes for all construction projects.

Regulating embodied carbon isn’t going to fix everything over night, but it would be a step in the right direction towards reducing carbon in construction. Yes, it would make it more difficult to build, but it would also force an industry that’s resistant to change to consider a different approach. And maybe that’s exactly what we need.