Carbon in construction: setting the standard for 2026 and beyond

BCIS executive director, James Fiske, summarises progress on carbon in 2025 and shares his thoughts on the launch of version one of the UK Net Zero Carbon Buildings Standard in early 2026.

Carbon in construction: setting the standard for 2026 and beyond

It’s been a yo-yo year for construction and the wider built environment sector, one defined by inconsistent output growth, planning delays and an economic resurgence that never quite materialised.

A carbon mandate still drifts in the ether despite progress on the UK Net Zero Carbon Buildings Standard (UKNZCBS) pilot and AECOM’s report on embodied carbon.

Autumn’s Carbon Budget and Growth Delivery Plan fell short of anything dramatic. Instead, the pudding was underbaked and underwhelming.

At the same time, new data has shown our sector’s scope 1 greenhouse gas emissions are travelling in the wrong direction.

Clearly, 2026 has a lot of catching up to do.

But what better springboard to regain momentum on a carbon front than the official launch of UKNZCBS Version 1?

It will be a huge moment for the built environment and the UK alike – the first time we’ll have a singular, national framework for verifying net zero carbon aligned buildings.

It’s the culmination of months of hard work.

In the past year, the Standard has been road-tested across more than 200 real-world projects with feedback collated on the achievability of its criteria published in a December pre-launch update⁽¹⁾.

On the whole, it appears to be hitting the right notes.

67% of participants in the piloting phase said the limits for upfront embodied carbon were at the right level for new works; 65% gave the same response for the operational energy limits in new buildings.

Certain thresholds may need more tinkering.

For instance, more than half of participants felt the renewable electricity generation targets were too ambitious and over one-third (39%) said they wouldn’t be able to gather and submit all material quantities as required by certain sections of the Standard relating to embodied carbon.

Other challenges include the Standard’s compatibility with pre-existing standards.

This has been a significant focus area during piloting; at a recent Chartered Institution of Building Services Engineers conference, Katie Clemence-Jackson, CEO of UKNZCBS, confirmed efforts are ongoing to minimise the extra work of achieving multiple standards at once. In other words, determining how standards like BREEAM, Passivhaus and NABERS UK can align with the Standard.

But fine-tuning is to be expected on a framework as large-scale as this one and piloting has proven its practical application.

It’s certainly a positive end note to a choppy year for our sector.

The challenge ahead will be developing a culture that matches the Standard’s progressiveness.

Demand growth for green real estate⁽²⁾ is declining globally and as a country we still lack a central carbon database, consistency in the collection and use of high-quality carbon data, and unity over who should conduct carbon assessments and how.

2025 saw a landmark report from AECOM making these very recommendations. We’re still awaiting a response from the government on this report and while full implementation on suggested actions is unlikely in the near term, acknowledgement of the report and some indication of the measures it plans to get behind would be welcome.

On a more personal level, the ground covered in Built Environment Carbon Database (BECD) developments and the BCIS Life Cycle Evaluator (LCE) this year are proof that opportunities to augment data quality in our sector are there for the taking.

The evolution of both BECD and LCE will continue in the coming year and coupled with the UKNZCBS rollout, are at the forefront of decarbonisation progress.

Alone, the Standard cannot force the required cultural shift but it’s certainly a cue to government and industry to embrace a more clinical, more meaningful approach to cutting carbon.

At this stage, it’s a prompt we cannot afford to miss.

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^{(1) UK Net Zero Carbon Buildings Standard – Pre-Launch Update 2 – December 2025 – here}

^{(2) RICS – Sustainability report 2025 – here}