It’s like green buildings 2.0 as the building and construction industry shapes up for one of its most dramatic challenges yet – a transition to net zero embodied carbon emissions with a 2050 deadline.
The World Green Building Council has released a new report to guide the global building sector to net zero embodied carbon emissions by 2050, and it already has the support of major industry players in Australia such as Frasers Property Australia, AECOM and WSP.
As it stands, the greenhouse gas emissions released when making building materials and during construction – known as embodied carbon or “upfront” carbon emissions – make up 11 per cent of the 39 per cent total emissions that the building industry is responsible for.
The industry has traditionally focused on the operations side of the equation (currently responsible for 28 per cent of total built environment emissions) and buildings are becoming more efficient as a result.
But with the global building stock expected to double in size in 40 years this will put embodied carbon on track to make up a much larger proportion of the total carbon footprint of new construction (as much as 50 per cent between now and 2050).
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So as part of World Green Building Week, the WorldGBC is calling for an ambitious 40 per cent less embodied carbon emissions by 2030 and 100 per cent net zero emission buildings by 2050.
The vision has the support of the Green Building Council of Australia, Australian Sustainable Built Environment Council, the Infrastructure Sustainability Council of Australia and major city councils such City of Melbourne and City of Sydney.
Notably, companies such as LafargeHolcim – a global building products company – has also endorsed the plans, as have other major companies in Australia such as AECOM, Atelier 10, Cundall, Edge Environment, Frasers Property Australia, Integral Group, Interface, JLL, Multiplex Global, RDT Pacific, Shaw Contract, thinkstep Australasia and WSP.
“We have had a strong focus on operational carbon emissions. Now it is time to boost our efforts to reduce embodied carbon emissions as well,” GBCA chief executive officer Davina Rooney said.
“In Australia we are already planning for a net zero carbon future – and better – with many of our members leading the way globally in terms of both innovation and commitment to a lower emissions future,” Ms Rooney said.
Of the 81 organisations globally to endorse the ambition outlined in the report at this early stage, twenty are GBCA members.
The hard road ahead to zero embodied carbon
So how does the WorldGBC propose the world get there? It’s not going to be easy thanks to the dispersed and complex nature of carbon-intensive building supply chains. At present, there’s only a handful of buildings worldwide that are net zero embodied carbon.
According to the report, it will be need to be a collaborative effort that will involve organisations, policymakers, investors, developers, designers and materials manufacturers.
The plan calls for embodied carbon reduction targets and legislation from government and cities, as well as roadmaps to kick things off. There will need to be improved processes to calculate, track and report embodied carbon.
The transition will rely on step change thinking in how the industry builds things, including making the most of existing buildings rather than building something new (The Fifth Estate has a feature coming up on this topic) and the circular construction techniques where building components are produced so that they can be cleanly separated for later reuse.
The pressure will also be on for carbon intensive building materials such as concrete and steel to innovate and lower the carbon footprint of their products. It was recently found that these two materials alone contribute more than half the carbon footprint of both residential and non-residential construction in New Zealand.
But there is no shortage of innovative alternatives, at least for cement. High blend cements, geopolymer cement and mineral carbonation are all viable options, with “institutional barriers” largely stopping widespread take up of these low carbon options.
There will likely be a key role for materials such as sustainably sourced mass timber – a renewable resource that stores carbon – in the transition to zero embodied carbon.
According to WorldGBC chief executive officer Cristina Gamboa, the report was a “solution focused response to the urgent need” to significantly reduce upfront emissions in building and construction, and to increase demand for action on carbon-intensive materials and industries.
“With the support of our global network and the endorsements we have received for the report, we are confident that we can stimulate market demand and facilitate radical whole value chain collaboration that will be truly transformative and benefit both people and planet,” she said.