CARBON TRIGGERS: Ahead of our Carbon Triggers Big Debate on 25 August, we asked one of the few sources keeping tabs on policy direction across the nation, the Green Building Council of Australia, to paint a picture of the state of play, and to outline some of the sentiment that underpins one of the most challenging aspects of the green building industry.
Ask Jorge Chapa from The Green Building Council of Australia what his position is on ripping down existing buildings and he’ll give you one of his classic spirited turns of phrase: “The first answer is that we definitely would want to see policies that encourage maintaining buildings that are still serviceable, right? Like we don’t want to people tearing down buildings just for fun and giggles, right?”
The value of maintaining embodied carbon, he continues is “unquestionably 100 per cent true”.
Finding a way to reward this in the Green Star reset of 2020 was central to the task but as another green building advocate noted in a related conversation recently there’s also buildings well past their use by date – or full of asbestos or plagued by fire hazard for instance.
The GBCA, says Chapa who is the organisation’s chief impact officer, spends a lot of energy “advocating for climate action”. “We have policy requirements in the entirety of the built environment on energy efficiency and operating emissions, from the building code to sustainable finance.”
In the past, getting operating emissions down was incredibly important.
The challenge was “gigantic”, he says, so there was little focus on embodied carbon. “There is nowhere in the [building] code or any other regulation for a building to reduce its emissions from refrigerants, for example. There also isn’t any regulation at a national or state level for buildings to reduce their embodied carbon emissions.”
The work has fallen on voluntary rating tools like Green Star, which has been driving action on reducing emissions from both for some time, Chapa says.
The requirement came into Green Star in 2020, but it’s an immensely tricky issue.
“You need to generate a lot of demand for lower embodied carbon to make reductions worthwhile for manufacturers,” Chapa says, because there’s a limit to how much you can do if demand isn’t there.
So policy action can be a solution. While the previously “harmonious” aims of the NCC seem these days to be falling apart (our view) might the big city councils pick up the slack by mandating some form of maximum carbon in new builds as the London Plan has done?
Chapa thinks the cities are limited in their power, but the National Construction Code and the states are not. The NCC would be the best place to put in such a requirement because it would mean “every building in Australia has to deal with it”.
In fact, the GBCA “advocated strongly” for the National Construction Code to start dealing with embodied carbon.
“NatHERS [the housing rating system] doesn’t but it could.”
“NatHERS [the housing rating system] doesn’t but it could.”
NABERS, the environmental rating system, is working to create benchmarks for embodied carbon and these can be used to build a policy platform for the non-residential sector, he says
The states could also address embodied carbon emissions, and in fact BASIX environmental assessment system for housing in New South Wales already requires the measurement of embodied carbon.
The challenge was “gigantic”, he says, so there was little focus on embodied carbon.
The states also have significant control over their own projects “there is a lot of work happening in the infrastructure sector.”
Infrastructure NSW in particular, where we understand a lot of work is on the way and will soon be revealed.
“We tend to think of the infrastructure sector as like rails and bridges, right? But Infrastructure NSW deals with a lot of other things like schools and hospitals.
“When the infrastructure bodies say, ‘hey we care about embodied carbon’, it turns out a lot of people have to care about embodied carbon.”
It’s also a positive that federal government procurement policies have requirements for Green Star buildings, which requires reductions in embodied carbon.
Where is opposition coming from?
“I don’t think anyone opposes it per se,” Chapa says. “It is just a much more difficult and trickier set of emissions to reduce than energy.”
Among the first difficulties is that there are no good benchmarks to kick off such a program of change. For now, it’s still very much a case of trying to get all the pieces to come together.
It’s been a decades long effort “There was a genuine lack of information on the impacts from materials when we started asking for life cycle assessments (LCA) in Green Star in 2013.
While the previously “harmonious” aims of the NCC seem these days to be falling apart (our view), might the big city councils pick up the slack by mandating some form of maximum carbon in new builds as the London Plan has done?
“Back then there were few environmental product declarations (EPDs). Information was limited, particularly for Australia. Generating incentives for this information through Green Star helped create a logical interest in embodied carbon. There was also little industry knowledge and expertise”
“It’s taken a long time to build the sector’s capacity and create the needed information. And to be clear, there are many others who have pushed for this to happen as well alongside GBCA”
Key though is that Chapa believes that “We’re pretty much now at the point where we can put in place all of these policies to execute on this.”
“Only a few years back it would have been very difficult to know the embodied carbon content of steel made in Australia. Now it’s much easier.
“There’s EPDs for products everywhere. Those are the things that we needed to build up”.
One option to start with is to get carbon mandates for larger buildings – say of more than 5000 square metres – because these are the ones most likely to have capacity to do the work involved.
“The point is we need to start now”
Wildly unfair criticism of methodologies
The criticism of the lack of consistency in embodied carbon methodologies Chapa says, is “wildly unfair”.
“When we do embodied carbon calculations, we’re expecting a level of precision that does not exist. “We want like three decimal points worth of precision.” While what’s important is heading in the right direction.
“The intention with embodied carbon policy isn’t to be accurate. We’re not trying to be 100 per cent accurate. We’re trying to move direction so that on the aggregate everything is going down.”
It’s the philosophy that underpinned Green Star, he says.
“We’ve had to do this stuff without having a lot of accurate data for a long time for a lot of things.
“If we wait for perfection, it makes it impossible to start.”
Following is an assessment of embodied carbon policy around the nation produced by Shay Singh, head of policy at the Green Building Council of Australia.
Voluntary
- Green Star introduced a requirement for upfront embodied carbon reductions of at least 10 per cent compared with a typical building in order to get a rating, with additional reductions for a 6 Star rating. This requirement is present in Green Star buildings (released 2020), Green Star Communities v2 (released 2023) and Green Star Fitouts (released 2025). In 2025, Green Star Buildings increased the requirements and aligned rules with NABERS based on joint work. Since 2020, more than 1000 buildings registered for Green Star now have to deal with reducing their embodied carbon. As part of the rebalance of the rating system, major refurbishments and reuse are heavily rewarded in the rating system as well.
- NABERS Embodied Carbon launched in 2024 and allows new buildings to measure and compare upfront embodied carbon using verified data, with a star rating where enough benchmarking data exists. The partnership allows broad alignment between NABERS Embodied Carbon and Green Star.
Commonwealth
- The main lever at the federal level is the Environmentally Sustainable Procurement Policy, which requires Australian government agencies to build environmental sustainability into procurement. For major construction procurement, it promotes low-embodied-carbon materials and circularity, drawing on evidence such as Environmental Product Declarations, Green Star and IS Rating
The National Construction Code
While building ministers around the nation agreed in June 2024 to a voluntary pathway in NCC 2025 for commercial buildings to measure and report embodied carbon using the NABERS method, that’s shifted since. Following the Commonwealth’s August 2025 announcement that no further residential changes to the NCC will be made until mid-2029, aside from essential quality and safety measures, building ministers agreed in October 2025 that the voluntary embodied carbon provisions will instead be published as ABCB guidance, rather than sitting inside NCC 2025 as a formal pathway
See this website for all communiques from the building ministers’ meetings.
See also Part J1 Energy efficiency performance requirements and NSW J1V2.
- The infrastructure and transport ministers’ meeting have also been working on consistent whole-of-life carbon measurement across infrastructure and the built environment, engaging closely with both NABERS and Green Star methodologies to keep buildings and infrastructure approaches aligned
- Infrastructure Australia’s 2024 report recommended a nationally consistent approach to measurement and reduction of carbon, including procurement reform, as an input to the 2035 targets. The report highlights key areas of opportunity for governments to consider in the development of sectoral decarbonisation plans that will inform the Australian Government’s Net Zero 2050 plan and 2035 carbon reduction targets. See IA24_Embodied Carbon Report.
State leadership
- The NSW Decarbonising Infrastructure Delivery Policy requires government agencies to measure, manage and reduce embodied carbon on major projects, buildings over $50 million and linear infrastructure over $100 million. See Decarbonising Infrastructure Delivery Policy
- The NSW Sustainable Buildings SEPP adds embodied emissions reporting into residential development assessment (through BASIX) and supports NABERS Embodied Carbon pathways for non-residential buildings, with a focus on disclosure rather than mandated targets.
- NSW Building Sustainability Index (BASIX). The NSW planning tool in place since 2004 that sets minimum energy and water efficiency requirements for residential development. It provides the long-standing baseline that the NSW Sustainable Buildings SEPP builds on, extending the same planning framework to bring embodied carbon into view alongside operational performance. See BASIX.
