As professionals in architecture, engineering, and construction (AEC), your decisions significantly influence the environmental footprint of buildings. A recent study by Endrit Hoxha, Harpa Birgisdottir, and Martin Röck explores the climate impact of materials used in construction across the European Union (EU-27). Their comprehensive analysis, published in the journal Sustainable Production and Consumption, breaks down exactly why material choices at the design stage matter, and how much they weigh in the grand scheme of a construction project. The simple version is: they matter a lot, if the goal is minimising a project’s greenhouse gas (GHG) emissions.

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The study compiled data from Environmental Product Declarations (EPDs) to assess the Global Warming Potential (GWP) of materials. By categorising materials into groups such as aluminium, concrete, steel, and wood, the researchers highlight key contributors to GHG emissions and regional disparities, providing also a roadmap for more informed decision-making.

Key Findings from the Study

The study gathered 8,067 Environmental Product Declarations (EPDs) from a variety of datasets to assess the Global Warming Potential (GWP) of materials commonly used in construction. By categorising materials into groups such as aluminium, concrete, steel, and wood, researchers identified major contributors to GHG emissions and highlighted the disparities across regions and materials.

The Life-Cycle Breakdown

The study analysed emissions across different life-cycle stages of materials, revealing a striking trend: the raw material supply stage (A1) is responsible for around 80% of the total GWP of most materials. Other stages, including manufacturing (A3), transport (A2 and A4), and waste processing (C3), play significantly smaller roles. This means that the environmental impact of materials is largely locked in from the moment raw materials are chosen.

Examples of Material Impact

• Aluminium: The highest average GWP at 21 kg CO₂e/kg, with over 90% of emissions arising from the A1 stage. Recycling aluminium can mitigate its impact by up to 40%, showcasing the importance of circular design strategies.
• Concrete: Surprisingly, concrete displays one of the lowest GWPs (0.09 kg CO₂e/kg). However, this doesn’t tell the full story, as concrete’s high use volume and its indirect emissions from cement production still make it a significant environmental concern.
• Wood: A low GWP material with potential for carbon sequestration, but regional variations in forestry practices can affect its impact.

The Role of the A1 Stage: Why Early Choices Matter

The overwhelming contribution of the A1 stage to a material’s GWP underscores the importance of selecting materials with lower emissions during the design phase. For example, choosing regionally sourced or low-carbon alternatives to aluminium and steel can significantly reduce a project’s environmental impact from the outset.

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However, finding reliable and comparable data on materials can be daunting. Material databases often suffer from inconsistencies and errors. The original number of EPDs selected for the study was more than 32,000, but it had to be cut down to around 8,000 due to exactly this reason. Moreover EPDs can be difficult to access — as they are scattered across different portals and repositories — or interpret, as the formats are not always consistent.

This is where tools like revalu become indispensable. By consolidating material data, revalu empowers AEC professionals to make informed decisions with ease, ensuring that the right materials are chosen early on.

Why Does Concrete Have a Low GWP in This Study?

At first glance, concrete’s low average GWP may seem counterintuitive. The study’s results stem from the standardisation of emissions per kilogram of material. Since concrete’s density and composition result in a lower GWP per kilogram compared to high-impact materials like aluminium, its score appears favourable.

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However, concrete’s true environmental cost lies in its widespread use and the cement production process, which is a major source of CO₂ emissions globally. Cement manufacturing alone contributes roughly 8% of global CO₂ emissions. The high demand for concrete in infrastructure and construction magnifies its overall environmental footprint.

How revalu Helps You Make Better Choices

The study concludes that better access to material data is crucial for reducing the climate impact of construction. Here’s how revalu addresses this challenge:

• Centralised Data Access: revalu consolidates EPDs and material information into a single platform, removing the need to scour multiple databases.
• Early-Stage Integration: By providing reliable GWP data at the start of a project, revalu enables AEC professionals to select materials that align with environmental goals.
• Custom Comparisons: Users can compare materials side by side, considering factors such as GWP, net fresh water, or energy mix.
• Informed Decisions: With data that’s easy to access and interpret, revalu ensures that choosing low-GWP materials becomes an effortless part of the design workflow.

Conclusion

The study emphasises that reducing the climate impact of buildings starts with informed material choices at the design stage. By understanding the outsized role of the A1 stage and addressing data accessibility challenges, AEC professionals can make decisions that significantly lower a project’s overall GHG emissions.

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revalu provides the tools to bridge the existing gap between intent and action, empowering professionals to choose materials that meet both project requirements and environmental goals. With revalu, you have the data at your fingertips to design buildings that are not only efficient but also mindful of their long-term climate impact.

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Try the revalu platform at https://platform.revalu.io/
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Link to the original study: https://www.sciencedirect.com/science/article/pii/S2352550924003580?via%3Dihub
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