dRMM reflect on the UK NZCBS

We see the NZCBS as a pivotal change in our industry – with a huge buy-in from a range of stakeholders, this is sure to be the basis for best practice project briefings. It goes further than existing guidelines such as LETI and RIBA 2030 climate challenge by proposing limits and not just targets (an important distinction, now made clearer). Alongside the operational energy and embodied carbon that we are now accustomed to measuring, NZCBS addresses renewable energy generation, the need for fossil-fuel free developments and responsible refrigerant use, providing a more comprehensive and holistic building carbon performance assessment.

The NZCBS also has a wider range of typologies covered than LETI and RIBA 2030 had previously allowed for –  there are 13 different building sectors – which is hugely helpful for practices like dRMM who work on a broad range of projects. It also sets out methodology for mixed-use developments and for both retrofit and newbuild schemes.

Our sustainability team rapidly digested the extensive and technical documents and a week after launch, presented this to the dRMM studio, as a bitesize training session. The most important aspects of the NZCBS come from the reporting requirements and the refinement of our ability to claim ‘net zero’ on building projects. We must as an industry move towards measuring in-use and declaring terms like net zero only when these new criteria are met, to avoid greenwashing the wider public and to help support science-based targets being met. We as a studio signed up to Bennetts Associates Anti-Greenwashing Charter, and would encourage other architectural practices to do the same.

We can see a trend that the most recently completed projects are those that are closer to meeting the targets, reflecting shifting industry sustainability priorities in the past few years. WorkStack, our latest project, is the closest to passing the NZCBS criteria (although as there is no light-industrial workspace directly covered, we used the Office typology as the closest match). Here, despite specifying ‘lower’ carbon refrigerants, there is still some way to go before compliance is met. And there is not enough renewable energy generation on site to pass. The mass timber structure, fossil-fuel free, and largely passive-strategy building management system means there is compliance in three out of five criteria. We think this building would be relatively straightforward to convert to a ‘pass’ should the client be interested in attaining this.

While it seems feasible for us to meet the coming limits in the near future, the horizon does look challenging in the later years of the standard’s lowering limits. We expect there will need to be a paradigm shift towards a circular economy and bio based construction industry to be able to attain the 2050 targets for embodied carbon, while the operational energy limits rely on going beyond Passivhaus and a decarbonised grid to be possible.

Another discussion we had as a studio is how we can use these limits to inform our international projects, in particular those coming from our Berlin studio. There is no equivalent standard yet in the German market, and we see a generally widespread lack of similar initiatives in Europe in joining up science-based targets with industry benchmarks. We will in the meantime be using this as a benchmarking piece for our German studio projects.

In terms of next steps, there is a pilot launch event on 31 October, where we will have the opportunity to ask the NZCBS team more questions, followed by a year of pilot testing before Version 1 is launched in late 2025. From all of us at dRMM, we want to say a big thank you to all those industry professionals who have developed this landmark piece of work. We were pleased to play a very tiny role in supporting it and are excited to set about meeting the challenge you’ve set us!