The UK Net Zero Carbon Buildings Standard Is Here: Are You Ready?
Francesca Wilkinson explains how the new standard she helped create will reshape how buildings are designed, specified and delivered
At UKREiiF, I joined Katie Clemence-Jackson, CEO of the UK Net Zero Carbon Buildings Standard; Richard Bowen-Ling, Head of Programme Delivery - Sustainable Communities for Learning, at Welsh Government; and Chris Williamson, President of RIBA, to discuss a significant development in our industry's journey to net zero.
A recurring theme throughout our conversation was the importance of having a single, credible definition of what a net zero building actually is.
As Katie explained, organisations have until recently been largely free to define net zero for themselves. While many projects were driven by genuine ambition, this created inconsistency across the industry and limited accountability. The new Standard provides a single, industry-backed definition that can be independently verified.
Developed by eight founding organisations and more than 300 industry contributors, the standard was published in March following an extensive pilot phase. Importantly, it is not a prescriptive design guide. Instead, it focuses on measurable performance outcomes, covering both operational energy and embodied carbon across new build and existing buildings.
That matters not only in meeting the UK’s carbon commitments, but in giving customers greater confidence in a building’s energy use, with lower energy demand, more predictable operating costs and better evidence to inform future investment.
What stands out to me is the balance between ambition and practicality. The standard's requirements are aligned with the UK's carbon budgets and ambitions to limit global warming to a 1.5°C trajectory, but they are also grounded in real-world performance data from hundreds of buildings.
Rather than relying solely on design predictions, certification is based on a full year of metered data, shifting the emphasis from design-stage ambition to proven performance in use.
Chris highlighted how this reflects a broader change across the sector, noting that RIBA now requires in-use performance evidence for its regional awards and the Stirling Prize.
Richard echoed this from the customer perspective, describing accountability as a key consideration for public sector organisations. Rather than sustainability ending at practical completion, buildings need to continue to demonstrate performance long after handover.
Richard then shared how these principles are being applied in practice at Glyn-coch Primary School in Rhondda Cynon Taf, a project delivered by Willmott Dixon and funded through the Welsh Government's Sustainable Schools Challenge.
From the outset, the project targeted Passivhaus certification, BREEAM Outstanding, Building with Nature accreditation and a commitment to significantly outperform embodied carbon benchmarks. Net zero was treated as a fundamental project objective rather than an additional requirement.
That approach shaped many decisions throughout delivery, including the use of Welsh and British timber, greater cement replacement and maximising on-site renewable energy generation.
The project also demonstrated that delivering better-performing, lower-carbon buildings is rarely straightforward. For example, catering requirements linked to Wales' universal free school meals policy increased energy demands, while the compact building form required for Passivhaus limited available roof space for solar panels. These challenges were overcome through collaborative problem-solving, including installing additional PV panels on a south-facing canopy. Richard’s key message was that these requirements need to be considered together while the design is still flexible.
We also explored why asset owners should invest in net zero standards. Beyond the environmental benefits, there is a compelling business case centred on risk reduction, operational performance and long-term value.
Too often, buildings fail to perform as intended, leaving owners exposed to higher energy costs and uncertainty around future performance. By requiring verification of actual energy use, the standard can help bridge that performance gap.
This reflects our own experience through Willmott Dixon’s Energy Synergy® service, which uses post-occupancy monitoring to help customers understand whether their buildings are operating as intended. During the discussion, we shared examples of the value of this approach, ranging from identifying underperforming solar installations to helping customers reduce long-term energy costs.
The standard also recognises the importance of retrofit. Its criteria are designed to accelerate improvements to existing buildings, and many pilot participants found they were closer to compliance than expected. Where buildings do not yet meet the standard, a new performance evaluation provides a clear roadmap for improvement, helping owners understand where they are today and what actions they can take next.
The audience raised thoughtful questions around contractual arrangements, offsetting and supply chain readiness. We heard that guidance and template clauses are being developed to help embed the Standard into procurement and delivery processes. The panel agreed that legislation, early engagement and industry leadership will all play a role in driving wider adoption.
When asked for one piece of advice, the panel was unanimous: introduce the standard at the very start of a project and keep it at the centre of decision-making throughout. As the examples shared during the session demonstrated, the earlier net zero is embedded, the easier it becomes to deliver meaningful, measurable outcomes.
My thanks to my fellow panellists and everyone who joined us at UKREiiF for a thought-provoking discussion on the future of net zero buildings.