The Data Quality Dilemma in Embodied Carbon Accounting: A Critical Challenge for Australian Sustainable Building Practices
As Australia accelerates its transition to a net-zero built environment by 2050, the focus on reducing embodied carbon—the greenhouse gas emissions tied to material production, transportation, construction, and disposal—has intensified. However, a persistent challenge threatens this progress: data quality issues in embodied carbon assessments.
Why Embodied Carbon Data Quality Matters
Embodied carbon makes up 16% of Australia’s built environment emissions, but this number could rise to 85% as operational energy efficiency improves, making its accurate measurement critical for achieving climate goals. Yet, there are key issues with the prevailing methods of calculating these emissions, which may undermine sustainable building practices and hinder the transition towards a decarbonised built environment.
1. Lack of Usable Product Data
The environmental impact of construction materials is usually stored in Environmental Product Declarations (EPDs), which are predominantly in PDF format. This methodological inaccessibility adds another layer of restriction for data users, in addition to the required domain knowledge and technical jargon. So far, most databases on the market only cover a fraction of the published EPDs, with even fewer products available for the ANZ region.
2. Over-Reliance on Generic Emission Factors
Given the data barrier, many building projects rely on generic emission databases like EPiC or AusLCI. This presents two problems. First, generic databases reflect only the industry baseline, and relying solely on generic data will never help the industry achieve carbon reduction. Second, using generic data is insufficient to justify the carbon reduction efforts of a project, as the actual embodied emissions are arguably misrepresented. As such, generic data only offers a temporary solution to prepare the industry for higher standards in the future.
3. Acceleration in EPD Publishing Under Decarbonisation Drives
With regulations tightening and standards improving, it is only a matter of time before the industry embraces product-specific data for embodied carbon measurement. That said, the gap to be filled is widening rapidly as EPD numbers are soaring, particularly in the past three months. To align with the vision of building decarbonisation, construction professionals desperately need an affordable solution for accessing usable product embodied carbon data.
The Impact of Generic Data: A Case Study in Residential Construction
Background
A 2023 study analysed embodied carbon in three single-storey Australian residential homes (200–240 m²) using One Click LCA software. The results showed embodied carbon intensities of 193–233 kgCO₂e/m², with concrete and aluminium identified as major contributors.
The Problem with Generic Assumptions
The study relied on a mix of local and generic data. For instance:
Concrete: The EPiC database was used, but if the team had defaulted to AusLCI’s average (30% higher), the results would have overstated emissions by ~60 kgCO₂e/m².
Aluminium Windows: Generic data often ignores regional energy mixes. Australian aluminium production, heavily reliant on coal power, has a carbon footprint 2–3 times higher than hydropower-based production in Europe. Using global averages would mask this critical issue.
Consequences of Poor Data Quality
Misguided Material Substitutions The study recommended replacing aluminium windows with low-carbon alternatives. However, without localised data, designers might prioritise materials perceived as "green" (e.g., timber) without accounting for transport emissions or sourcing practices.
Ineffective Policy Benchmarks Infrastructure Australia warns that inconsistent data could complicate national decarbonisation targets. For example, upfront embodied carbon in buildings is projected to reach 37–64 MtCO₂e per year by 2029, but without accurate benchmarks, progress towards the recommended 23% reduction by 2027 will be unverifiable.
Erosion of Stakeholder Trust Disparities in carbon inventories—such as timber’s biogenic carbon storage being counted variably—create confusion. A 2024 study on office buildings highlighted that "temporal net-zero" claims depend heavily on methodological choices, risking greenwashing accusations.
Pathways to Improved Data Quality
Adopt Standardised National Databases Infrastructure Australia advocates for a national emissions factor database to unify methodologies and ensure transparency. Initiatives like the NABERS Embodied Carbon tool and the EPiC Database are steps forward but require more extensive product datasets.
Prioritise Environmental Product Declarations (EPDs) EPDs provide material-specific data validated for regional conditions. Tools like the Low Carbon Materials Hub's DB v3 integrate EPDs, enabling designers to compare suppliers and reduce reliance on averages.
Educate Industry Stakeholders Training programs for architects, engineers, and policymakers—such as those proposed by the Infrastructure Net Zero Initiative—can bridge knowledge gaps and foster confidence in low-carbon solutions.
Conclusion: A Call for Rigour and Collaboration
The case study underscores a stark reality: generic data risks derailing Australia’s net-zero ambitions. Without accurate, localised inventories, even well-intentioned sustainability efforts may fall short. By standardising methodologies, leveraging EPDs, and fostering cross-sector collaboration, the construction industry can turn embodied carbon from a liability into a lever for transformative change.
At Low Carbon Materials Hub (LCMH), we make it our mission to bring better data to the building industry to ensure embodied carbon reductions are meaningful and measurable. To achieve this, we have leveraged cutting-edge AI technology to deliver the latest LCMH Database v3, which now covers 11,000+ construction materials that are 100% verified and backed by EPDs, making it the most extensive embodied carbon database in the ANZ region. Tools like this can provide the transparency and accuracy the industry desperately needs.
As the Embodied Carbon Inventories scoping review concludes, "If the trustworthiness of the data is questionable, so too are the outcomes." For Australia’s sustainable future, resolving data quality issues isn’t just technical—it’s existential. If you are also struggling with poor carbon data quality or have thoughts about changing the status quo, let’s talk and join forces to enable more informed decarbonisation decisions and, therefore, a more sustainable built environment!
