When we talk about reducing carbon emissions, operational energy use often steal the spotlight. But lurking in the background is a massive emissions culprit—building materials. From the steel framing a skyscraper to the concrete of your local shopping mall, these materials are central to the built environment. Yet their environmental impact is often overlooked, despite being a major contributor to global emissions.
In recent years, both GBCA and NABERS have entered the game. But we're still in early days for learning how to measure and manage upfront carbon emissions in our building products.
Concrete is one of the largest offenders, responsible for around 8% of global CO2 emissions. The energy-intensive process of making cement, the main component of concrete, requires heating limestone to over 1,400°C—releasing vast amounts of CO2. Steel also plays a major role, contributing 6-9% of global emissions, largely due to the carbon-heavy production process that uses coke (a form of coal) to extract iron ore. While timber is often seen as a greener alternative, its carbon impact is significant, especially when considering deforestation and waste inefficiencies.
Below these heavy-hitting structural products are tens of thousands of smaller products all making an individually modest and collectively significant impact on overall supply chain emissions. We haven’t even begun to address them.
But the environmental footprint doesn’t end with production. Transporting these heavy materials—often over long distances—adds another layer of emissions. Building materials are bulky and weighty, resulting in high-carbon transport just to get them to the site.
Why does this matter to you?
The building and construction industry is facing a huge challenge, with 90% of construction company emissions classified as scope 3—emissions from materials and transport, largely out of a company’s direct control but still within their sphere of influence. Furthermore, only around 10% of building products in Australia have a verified Environmental Product Declaration (EPD). Given that EPDs are complex and costly to obtain, experts are beginning to acknowledge that the current system isn’t sustainable at scale. There must be a better way to ensure transparency and support sustainable decision-making.
Sources:
Pandit, J, Watson M and Qader, A, 2020. Reduction of Greenhouse Gas Emission in Steel Production Final Report. CO2CRC Ltd, Melbourne, Australia, CO2CRC Publication Number RPT20-6205. https://www.resources.nsw.gov.au/sites/default/files/2022-11/report-reduction-of-ghg-emissions-in-steel-industries.pdf
CDP Technical Note: Relevance of Scope 3 Categoriesby Sector, https://cdn.cdp.net/cdp-production/cms/guidance_docs/pdfs/000/003/504/original/CDP-technical-note-scope-3-relevance-by-sector.pdf
Jonas Bengtsson 2024. Accelerating Carbon Footprint Disclosure and Decarbonisation in the Built Environment, https://www.edgeimpact.global/insights/accelerating-carbon-footprint-disclosure-and-decarbonisation-in-the-built-environment