A recent study explores the potential of building materials to store significant amounts of carbon dioxide (CO2), presenting a new avenue for addressing climate change. By substituting conventional materials with carbon-storing alternatives, such as bio-based plastics, alternative cements, and biocharBiochar is a carbon-rich material created from biomass decomposition in low-oxygen conditions. It has important applications in environmental remediation, soil improvement, agriculture, carbon sequestration, energy storage, and sustainable materials, promoting efficiency and reducing waste in various contexts while addressing climate change challenges. More fillers, the built environment could sequester up to 16.6 billion tonnes of CO2 annually—approximately half of the global CO2 emissions recorded in 2021.

The study highlights two key advantages of using building materials for carbon storage: their large production scale and their longevity. Materials like concrete aggregates, despite their low carbon storage potential per kilogram, represent the largest overall potential due to their vast global usage. Similarly, timber and bio-based plastics contribute to carbon storage through their natural properties and adaptability to construction.

Replacing conventional materials requires integrating bio-based or mineralized alternatives. For example, biochar fillers in cement and bio-based plastics derived from agricultural residues are promising options. While this shift demands increased feedstockFeedstock refers to the raw organic material used to produce biochar. This can include a wide range of materials, such as wood chips, agricultural residues, and animal manure. More and energy, these alternatives can complement other carbon dioxide removal strategies, reducing reliance on geological or ocean storage.

Challenges remain, including scaling production, managing costs, and aligning materials with existing safety and performance standards. However, adopting these solutions could significantly reduce the construction sector’s carbon footprint and play a crucial role in meeting climate targets.

This innovative approach underscores the need for policy support, investment in sustainable technologies, and the integration of carbon storage into building practices as we strive toward a net-zero future.

SOURCE: Van Roijen, Miller, & Davis (2025) Building materials could store more than 16 billion tonnes of CO₂ annually. Science. https://doi.org/10.1126/science.adq8594