Home Property Australia Upfront emissions need to be addressed ‘to secure a sustainable future’

Upfront emissions need to be addressed ‘to secure a sustainable future’

  • June 07, 2023
  • by Property Australia
Lendlease Head of Sustainability Australia Ann Austin.

Australia’s carbon emissions from construction are projected to surge from 16 per cent to a staggering 85 per cent of the total building emissions by 2050, unless proactive measures are taken to improve material choices and construction practices, according to a new report.

The Green Building Council of Australia and Lendlease have unveiled a guide aimed at curbing upfront carbon emissions in new buildings and extensive renovations.

Upfront carbon emissions are produced during a building’s material production and construction activities before its use.

The ‘A practical guide to upfront carbon reductions’ guide emphasises that 25 per cent of emissions stemming from a typical building result directly from the products and materials employed in its construction, and the irreversible nature of these emissions underscores the urgency for action.

GBCA Chief Executive Davina Rooney said we need to address upfront emissions now to ensure we secure a sustainable future for generations to come.

“Put simply, the buildings of today need to address the emissions of tomorrow,” Ms Rooney said.

“Reducing our upfront emissions on future projects will have a material impact on reducing climate change, will create benefits for investors who are looking for assets with a clear decarbonisation pathway, and will help to achieve Australia’s decarbonisation goals,” Ms Rooney said.

Lendlease Head of Sustainability Australia Ann Austin said its construction business plays a key role in two core aspects of the company’s ‘Mission Zero’ journey, phasing out the use of fossil fuels in construction, and eliminating upfront embodied carbon in our building materials.

“While we’ve delivered 26 engineered timber buildings globally, our research shows more needs to be done to decarbonise steel, concrete and aluminium – the three leading materials that typically contribute to more than 70 per cent of a building’s embodied carbon footprint.

“This guide will play an important role in supporting customers, supply chain and the broader industry to overcome barriers, collaborate and accelerate radical industry transformation to support a 1.5°C future.”

Ms Rooney said there are some great examples of projects that have slashed their upfront emissions, but to meet our emissions reductions targets we need this change to happen at scale.

“Lendlease’s project team for 25 King Street in Brisbane made impactful decisions in the design phase to swap out materials like concrete and steel, for low carbon options like engineered timber – resulting in upfront emissions savings of almost 40 per cent,” Ms Rooney said.

The key upfront carbon reduction design initiatives at 25 King Street included:

  • Engineered timber was used in lieu of carbon intensive concrete and steel for structural columns and beams
  • Minimalist internal finishes with CLT cladding and flooring with no suspended ceilings systems throughout
  • 40 per cent reduction in overall Portland Cement use

Ms Rooney points to another case study from the guide, Quay Quarter Tower in Sydney’s CBD which saved over 12,000 tonnes of CO2 emissions during construction through retaining 65 per cent of the 1976 building’s original structure and 95 per cent of its core.

“It was just five years ago that we were only focused on reducing the operational carbon of an asset. As the grid continues to decarbonise, projects like Quay Quarter Tower show us that it is possible to reduce the emissions from construction, and there is value in redeveloping existing assets,” Ms Rooney said.

The Life Cycle Assessment conducted by the team demonstrated a saving of over 12,000 tonnes of CO2e- of upfront carbon emissions from the reuse of concrete alone compared to a Reference Project. The structural carbon footprint of the building was estimated at 247 Kg CO2/m2 gross internal area. This is in contrast to 600 – 700 Kg CO2/m2 for a new building with full demolition of an existing building.

The report says a 10 per cent reduction in upfront carbon is generally achievable with the use of low carbon materials and is minimal to cost neutral.

A 20 per cent reduction will require most than just substituting materials for a low carbon option, according to the report, with more collaboration needed between stakeholders to dematerialise the building through design optimisation and the reuse of existing buildings will be needed.

A 40 per cent reduction is “ambitious but achievable,” according to the report.

This reduction can be achieved by reusing existing buildings or by using reused components or low carbon materials are part of all new building elements.