‘This is our call to arms’ – understanding the new net zero standard

“This is our call to arms,” says David Partridge, the Related Argent chairman who has led a ground-breaking, cross-industry initiative to produce a UK Net Zero Carbon Building Standard. “Please put your projects forward and test it.” After a more than two years of work, the gates are now open for between 50 and 100 projects across 14 sectors to test the pilot version of the standard, which was published on 24 September. Reaching this point has been a mammoth task involving collaboration between key industry organisations – BBP, BRE, the Carbon Trust, CIBSE, IStructE, LETI, RIBA, RICS, and UKGBC – and experts, with many individuals putting time in pro bono.  It has the potential to be a game-changer because until now there has been no single, agreed methodology for defining what “net zero carbon” means for buildings in the UK. Consequently, concern has grown that the area has been rife with spurious claims around the topic. Crucially, the standard has been created not just using industry data on what is achievable, but also cross-referencing this with top-down modelling of what is needed to decarbonise the industry in line with 1.5°C-aligned carbon and energy budgets. This involved a vast research initiative to create a complex model of the UK’s entire existing stock and future build-out rates in order to define what “net zero carbon-aligned” performance should be for operational energy use intensity and upfront embodied carbon for each subsector. “It’s now time to get into the nitty gritty of what the standard actually is, what it means and how the targets and limits are going to impact on the real world of designing, owning and operating buildings,” says Partridge, who is chair of the standard’s governance board. Assess your stock Katie Clemence-Jackson, an associate at building design consultancy Qoda, has led the standard’s technical steering group and says the team is now encouraging people to look at the standard and think about the buildings they have: existing buildings they think could be performing in line with the standard or buildings under development they’re looking to target the standard. [caption id="attachment_1258910" align="alignright" width="300"] David Partridge[/caption] Registration will open later this year and is likely to focus on four categories: buildings being designed, buildings being constructed, buildings that have reached practical completion and buildings that are in use. To achieve the standard verification, buildings must be in use but the pilot will assess how easy it is to apply it at those early stages. “It’s the first standard that’s covered net zero carbon in the level of detail that the industry has been calling for in terms of robustness. There are more requirements than some other pre-existing and perhaps less technically rigorous definitions,” explains Clemence-Jackson. “So it’s not a case of just saying ‘my building performs really well in operational energy’. It also needs to have information about its embodied carbon as well. People need to make sure they’ve got all that data available or work out how they would get it.” Testing will start in the new year. This real-life application will then be fed into version 1.0 of the standard. Some of the detail can be found in an annex to the 126-page pilot document, the most obvious being embodied and operational carbon limits. [caption id="attachment_1258911" align="alignright" width="300"] Katie Clemence-Jackson[/caption] Here you can find tables of upfront carbon limits for new works and for retrofit works based on the year of starting on site, broken down by sector. The limit on the carbon emission equivalent per sq m ticks down from now to 2050. For offices (whole building), for example, it drops from 735kg CO2e in 2025 to just 60kg CO2e in 2050. “We’re expecting it to become easier as materials decarbonise. We’re also expecting a level of upscaling and improvement across the industry,” explains Clemence-Jackson. Buildings will be required to have a life cycle carbon assessment carried out to demonstrate whether they are within these limits. There are also stepped limits for reportable works, namely fit-outs, for the office sector. “That was the only sector where we could get enough data for those – that was a fantastic piece of work. It’s important because it’s a known area where a lot of carbon gets emitted,” says Clemence-Jackson. Energy assessment Performance against operational energy use limits should, in theory, be more straightforward to assess, based on metred measurements. Expectations vary depending on whether projects are new-build, retrofits carried out in one go or step-by-step retrofits. Crucially, there are also reporting requirements for energy demand intensity. “Energy demand is such an important part of the net zero carbon story,” says Clemence-Jackson. “The [carbon] budget is associated with how much renewable energy we can generate as a country. The balance is being achieved at a national level. We don’t want to take up more than our fair share of that.” Elsewhere, the pilot covers everything from onsite renewables to operational water use; district heating and cooling networks to refrigerants. “There’s some really meaty stuff in there around how science-based this actually is and why it’s got the robust integrity that we want it to have and why people can rely on it when a limit says ‘that’s as much embodied carbon as you’re allowed to use in a building to qualify for the standard’. We want everybody to understand why,” says Partridge. The whole system will be underpinned by data reporting periods and annual re-verification. More than 700 people took part in roundtables and consultations, with carbon offsets being among key issues discussed. The outcome is that there will be the option to achieve verification with offsets – but buildings will be labelled as “net zero carbon-aligned” or  “net zero carbon-aligned plus offsets”. There will also be clear requirements for the types of offsets that will be accepted. Another key issue was the whole-building approach of the standard versus being able to delineate – for example, the landlord and tenant spaces within an office building, or the individual units within a retail park. For now, the standard is taking a whole-building approach, but work is under way to interrogate how delineation works in different sectors so it can be fed into future versions. The standard inevitably overlaps with aspects of existing systems, most notably NABERS (the National Australian Built Environment Rating System, which deals with operational performance) and BREEAM (the Building Research Establishment’s Environmental Assessment Methodology). Work is under way to enable people to avoid duplication. The team is exploring with NABERS what rating you would need to achieve to be deemed to satisfy the operational element of the new standard. “So if you’re doing that already, you can get a tick in that box, and then you can go and focus on the embodied carbon elements and the renewables and all the other things that the standard asks for,” Partridge explains. Similarly, they are in talks with BREEAM, which will roll out its own version 7 in 2025 so people don’t have to jump through the same hoops twice. Reading from the same page There is a recognition that the proliferation of systems has not served the zero-carbon agenda well. So the standard is working with everyone – LETI, BRE, RIBA, RICS and more. “We’re trying to get everybody on the same page, doing the same thing, calculating the same stuff in the same way, which would be nice, wouldn’t it? It would be so much easier for everyone,” says Partridge. But it’s not seeking to replace other well-regarded systems for measuring other things besides carbon – other aspects of environmental impact and social impact, for example. “Just being net zero carbon isn’t enough,” he adds. The working assumption is that projects and buildings able to demonstrate conformity and compliance with the standard will lodge their data with the Built Environment Carbon Database, which will be used to drive future versions of the standard. “We’ll be able to see what’s achievable in real life, how many people are getting there. The data will be anonymised but people will be able to see what is achievable,” Partridge explains. How the verification process will work and who will be doing the verifying are key aspects which Partridge hopes will fall into place next year. A tender process for organisations to become “verification administrators” is being worked up. “We need to have a long-term vision for what the thing’s going to look like in five years’ time and 10 years’ time and how that gets supported by the big institutions who, frankly, are the people who are going to be around in five years’ and 10 years’ time,” he says. “We want this to be something that becomes second nature to professionals in the built environment to be able to look to competent and trained individuals to be able to sign this stuff off – in the same way you would go to a building safety officer or a fire specialist or a Red Book valuer. There are professionals who are qualified to give specific certificates on all sorts of aspects of what we’re doing. We want to see where we sit in all of that lot and set that up for the future so that it’s got integrity, it’s bomb-proof.” Government policy There is a sense of optimism from both Partridge and Clemence-Jackson, despite the extent of the work ahead. “I’m feeling excited about the positive growth and development that can now happen in the industry now that we’ve got this definition that’s been agreed through such a massive collaboration across the built environment,” says Clemence-Jackson. There is hope it could inform government policy, with information already being provided to government departments on the standard so far. “What we would like to see is some alignment over time because the government is also committed to a net zero carbon target. Our standard has provided a body of research and learning about how that might be achieved. “A really good thing that we would like to see is the metrics that we have proposed starting to be monitored through legislation.” In the commercial world, Partridge says the standard is “pushing at an open door” for many stakeholders. Occupiers competing for talent, for example, want to demonstrate leadership in ESG, and contractors and suppliers want to show they can deliver the products that conform to this. “We want this to become the benchmark which people use, which investors insist on, which banks insist on, which developers insist on, which occupiers insist on. Most architects I have talked to love this because at last, someone is going to make it clear that this is worth doing.” He refers to the “golden flywheel”, which the standard wants to begin to turn for the sector. “This is the future that everybody wants to be a part of, but they want to be able to have one single measurement to demonstrate that they are doing the right thing.” The standard’s requirements Main image © Shutterstock