An upfront conversation about upfront carbon

“A quarter of a building’s emissions are locked in on the first day the occupants walk through the front doors,” says the GBCA’s Jorge Chapa. “Every project team gets just one shot to reduce the upfront carbon of their next building.”

Upfront carbon, once digression in the net zero building conversation, is now the main topic for discussion at every event, says the GBCA’s Head of Market Transformation. “Three years ago, we couldn’t get anyone to talk about upfront carbon emissions. Everyone was focused on operations. Now we can’t get anyone to stop.”

The logic behind this is straightforward. As the electricity grid decarbonises and more buildings are powered by 100% renewable electricity, the next big source of emissions is generated during construction.

The GBCA began championing lifecycle assessments of materials through a Green Star Innovation Challenge back in 2014. The Carbon Positive Roadmap, released in draft form in 2018, sent a louder signal to the industry. Since 2020 all new buildings seeking a Green Star rating have needed to demonstrate a 10% reduction in embodied carbon. By 2030, the benchmark will be a 40% reduction in embodied carbon.

The targets outlined in the Climate Positive Roadmap match the WorldGBC’s ambitions in its landmark report, Bringing embodied carbon upfront, which called for a 40% reduction in embodied carbon by 2030 and zero embodied carbon by 2050.

Tackling embodied carbon – which encompasses all emissions generated during a building’s lifecycle – is a colossal challenge. But as Jorge says, up to 80% of a building’s embodied emissions are generated upfront, during the product and construction stages.

“Upfront emissions, when spread across a building’s lifetime, may account for just 1 or 2% a year. They may seem minimal. But they add up to around 25% of a building’s total carbon footprint and they are fixed from Day One.”

In 2019, embodied carbon accounted for 16% of built environment emissions. Without action, this share will balloon to 85% by 2050. But action is underway.

The GBCA is collaborating with NABERS on the development of a new standard to measure, compare and certify embodied emissions. Read our interview with NABERS Director Carlos Flores to learn more. 

A plain English, practical guide to upfront carbon emissions is soon to hit the market. The guide, developed by Mott MacDonald with in-kind support from Lendlease, will help decision makers along the length of the construction value chain to understand the role they can play in addressing embodied carbon.

“The guide will step everyone from development managers to leasing agents through process of structuring a low embodied carbon project, from setting targets to drafting tender documents.”

A modelling guide is also in development with thinkstep-anz to align upfront carbon calculations. Jorge says the guide will be especially useful for atypical building typologies. “Comparing office buildings is one thing, but what if we are building a new Sydney Opera House? Having clear rules will help.”

The GBCA is also working with the product ecosystem to plug the information gaps and compile a consistent materials database, particularly in the building systems sector. “Consultants need to work with the same numbers. For building systems, we are working with CIBSE Australia to adapt the TM65 embodied carbon calculator. This methodology makes it easy to calculate the amount of upfront carbon for building systems, which will provide much needed information to building designers.”

Jorge is “heartened” to see how the conversation has shifted in a few short years. But achieving a 40% reduction in embodied carbon – the ambition set by the Climate Positive Roadmap – is “a huge challenge,” Jorge admits. “If we are going to address this challenge, we must face it upfront.”

How can we collaborate to overcome barriers and accelerate change to remove embodied carbon from the built environment and towards a net-zero future? Find out at our upcoming embodied carbon masterclass. Reserve your place here.