It’s often said change comes from within, and the industry is putting that to the test with a potentially radical set of net zero building standards of its own devising. Tim Clark reports
In a sector where incremental change seems to be almost baked into its very psyche, seeing a step change is rare. Construction and real estate isn’t always known as a leader in innovation.
However when it comes to net zero, the launch of a pilot set of standards in September could prove to be a true a game-changer. The Net Zero Carbon Building Standards (NZCBS) are a voluntary set of carbon standards which have been drawn up by the industry itself.
It’s a free-to-access technical standard that will enable the built environment to robustly prove that built assets align with the UK’s carbon and energy budgets.
Led by the chair of developer Related Argent, David Partridge, a swathe of industry experts has also contributed to ensure the new standards are robust, and deliver on the promise to drive down carbon emissions.
Organisations including BBP, BRE, the Carbon Trust, CIBSE, IStructE, LETI, RIBA, RICS, and UKGBC have joined forces to champion the initiative.
Tom Wigg, senior advisor, net zero carbon buildings at the UK Green Building Council (UKGBC) – who was a contributor to the new standard – believes that the industry will embrace the standards as it has had an instrumental input in drawing them up from within, rather than dictated to by government or planning policy.
As ambitious as they are, however, could it change construction as we know it?
Trustworthy benchmark
Wigg explains that when it came to low carbon solutions, the construction and property industry has been searching for answers for a while.
“When I joined UKGBC, a colleague had just finished market analysis, revealing industry demand for more robust verification,” he says.
“We conducted a survey with extensive input, including 400 survey responses and numerous workshops, the feedback showed a preference for transparent, independent standards. Industry didn’t want another opaque, for-profit scheme but needed an accessible, trustworthy benchmark.”
The standard sets out mandatory requirements for net zero carbon aligned buildings that could – if the rest of the UK building stock were to collectively implement compatible interventions – enable the UK real estate sector to stay true to the built environment’s share of our national carbon and energy budgets. This approach is defined by the term ‘Net Zero Carbon Aligned Building’ within the standard.
Offsets may be used to complement, but not replace, the mandatory elements of the standard, and may be used to achieve net zero carbon at the asset level. This approach is defined by the term ‘Net Zero Carbon Aligned Building (plus offsets)’ within the standard.
“Having a tangible roadmap, even in a pilot phase, allows for practical testing and benchmarking provides a clear framework for developers and property professionals to align with net-zero targets, ensuring that the path to carbon neutrality is well-structured and measurable,” says Tom Roundell Greene, head of sustainability at Carter Jonas.
“The NZCBS represents a significant step forward for the decarbonisation of our built environment. By having a single, unified standard, which is aligned with climate science, we have an objective and measurable way to assess how built assets are helping to deliver against the UK’s net zero goals.”
Others echo Greene’s thoughts.
“In short, this standard allows developers and asset managers to more accurately assess if an asset is in alignment with broader climate objectives, for all sectors and scopes in the UK market,” writes Theo Meslin, senior sustainability and energy consultant at Longevity Partners.
“The hope is that most developments would aim to comply with this standard going forward, pushing design teams to seriously work on tracking (and reducing) their embodied carbon and designing their buildings to have highly efficient energy performance in-use.”
Grassroots data
The first six months were critical as nine organisations worked in a collaborative effort to develop the ‘Net-Zero Building Standard’ concept.
“We didn’t want a top-down approach, so we gathered data from thousands of buildings, modelling what was feasible in the UK,” Wigg adds. “This grassroots data informed the standard, making it realistic yet ambitious.”
Embodied carbon – the emissions from materials and construction – is a core area of the new standards. Construction companies will need to measure and minimise emissions linked to the production, transport, and disposal of materials, as well as look to reduce the carbon that is used in construction of new buildings.
From offices to homes, the NZCBS has outlined ambitious targets broken down each year. The targets are set out as the emissions in kg for every square metre of a building’s gross internal space (GIA), which is outlined as kgCO2e/m2.
For example, the embodied carbon for a single family home is set at 430 kgCO2e/m2 in 2025. However this falls by around 30 kgCO2e/m2 each year onwards. By the end of the decade this will fall to 290kgCO2e/m2. This is a real jump on lowering carbon emissions.
Similarly, for whole building offices the level of 735 kgCO2e/m2 drops to 550 290kgCO2e/m2 by 2030. By 2040 it falls to 235 290kgCO2e/m2, and by 2050 it is as low as 60 290kgCO2e/m2.
The yearly limits will either drive change, or targets will be missed. What could a changed construction sector look like? Could concrete be obsolete by the end of the decade?
Material decarbonisation
“In the future, you are not going to be able to build a 100-storey mega-tower all clad in glass and air conditioners and meet the standard,” says Will Arnold, head of climate action at The Institution of Structural Engineers.
“There is a big reliance on material decarbonisation, we can use less materials than we dow now, and reduce carbon limits but the short answer is that materials need to change, concrete needs to decarbonise, the grey gloopy stuff we put in the ground at the moment needs to change. It may still be called concrete, but it will be a different material.”
Arnold says that the changes in client demand should prompt material suppliers to change their products. Low carbon-concrete – highlighted by Build in Digital earlier this year could become more mainstream in the UK faster than previously envisaged.
The standards are also expected to drive a shift toward low-carbon alternatives, like recycled steel, and sustainably sourced timber. Suppliers will likely be required to provide Environmental Product Declarations (EPDs) to ensure transparency around materials’ carbon impact. Companies may also begin to favour other construction methods such as modular or prefabrication to help reduce emissions and improve efficiency.
Huge interest
The standard has certainly piqued the interest of the sector. Since its launch in September the body which organised the standard held a webinar which was attended by over 2,500 professionals seeking more information on what it means for the construction, design and engineering sectors.
“The interest in this has been huge, especially from the construction industry in this standard,” Arnold adds. “I speak to architects already and clients are already asking design teams if they have a chance of meeting the standard [with their project].
“I expect to see clients and financiers looking for net zero carbon-aligned targets [written into design briefs].”
The standard is voluntary, however it may be that councils adopt similar carbon standards as part of local planning policies or reference them in any five-year plans they have.
“Local planning authorities are essential in embedding these standards. Some cities, like Cornwall and Bristol, have started requiring net-zero benchmarks in their local plans, ensuring projects meet strict energy and carbon limits,” Wigg adds. “The Net-Zero Building Standard aggregates data across thousands of buildings, providing a solid reference point for these local policies.”
Design principles could also change – and accelerate trends such as maximising natural light in buildings, as well as architects looking at passive solutions could also play a significant part in reducing carbon in new buildings and retrofits, as will the circular economy principles.
Encouraging the reuse and recyclability of materials after a building’s life cycle; this requires planning for dismantling or repurposing parts of the building when it is decommissioned, diverting waste from landfills and further reducing emissions associated with demolition.
“Ultimately, the standard brings forward a great deal of hard work defining what “best practice” looks like in the built environment, and what “Net-Zero” means,” Meslin says.
“It is not meant to be a low-hanging fruit, nor is it supposed to be impossible to achieve. Real data has been used to form this baseline, and real data will continue to be used to inform how this standard evolves into the future.”
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