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PRECAST CONCRETE ELEMENTS148 CPI %u2013 Concrete Plant International %u2013 2 | 2026 www.cpi-worldwide.comrelated with the applied stress. The results of the structural test suggest that the prefabricated walls are expected to support almost all buildings under Swiss norms [8]. Due to the promising resistance of these walls, compression load tests on full-scale walls would probably not result to failure even given the most powerful loading equipment of academic facilities of Switzerland.From research to industry recognition and adoptionBeyond academia where this research has been well recognised and awarded, this reuse of concrete rubble to make load-bearing walls has received international attention from the construction industry. It was notably selected for the 2026 World Congress of Architects (UIA) and for scaling it to many public infrastructure projects in Barcelona, following an international competition%u2019s winning proposal by SXL EPFL lead by Maxence Grangeot, and in partnership with architectural firm Baukunst. In Brussels, architects TEN Studio and Babini Geysen, working with the author, also won first prize for a new recycling centre design that incorporates reused demolition concrete. Other projects in Lausanne, Paris, Rennes, Parma, Zurich and more have adopted this system, whose execution is advised by Maxence Grangeot in collaboration with local partners. These successes highlight the growing interest within the construction sector to turn demolition concrete rubble into a valuable resource for the built environment. The high adoption rate of the method is likely also due to the pleasant aesthetics of the walls, reminiscent of traditional cyclopean stone masonry while offering a contemporary twist and a visually explicit image of reuse [12].Pragmatism of a new fabrication methodTo summarise, this research demonstrates how concrete rubble from demolition can be pragmatically transformed into a valuable construction material through the development of an accessible fabrication process for load-bearing walls. Using low-cost picture-based scanning and digital 2D masonry layout planning, the process minimises voids thus new concrete quantities, and thereby lowers environmental impact of concrete load-bearing walls. The physical load testing shows promising early results for slender walls capable of resisting typical compression forces, while keeping the entry level low by building on existing machinery and construction skills. The flatness achieved on both faces of the walls further enables the integration of additional building layers, extending the system%u2019s applicability. Further research is needed to assess building-physics interactions and structural performance under compression, eccentric and lateral loads.An underexplored opportunityPositioned within the broader challenge of material circularity, this research reframes concrete rubble as an underexplored opportunity rather than a waste, addressing the limited environmental benefits of conventional concrete recycling. Concrete rubble is identified as a local, low-carbon, and affordable resource well-suited to compression-based structures, offering new design freedom through the aggregation of irregular pieces without altering demolition practices. By combining accessible digital tools with a safe, scalable, and resilient upcycling process, the study demonstrates how load-bearing walls can be constructed with a significantly lower environmental impact than conventional concrete construction, while fitting within current construction logistics. The built demonstrators confirm the feasibility and environmental saving potential of this approach, highlighting a clear pathway for rapid industry adoption to expand its structural and architectural possibilities.Curious about the scientific publication and the latest updates on this research? Feel free to visit the regularly updated website: https://go.epfl.ch/rubble-reuse or scan the QR-code. nReferences[1] Giorgi S, Lavagna M, Campioli A (2018) Guidelines for Effective and Sustainable Recycling of Construction and Demolition Waste. In: Benetto E, Gericke K, Guiton M (eds) Designing Sustainable Technologies, Products and Policies: From Science to Innovation. Springer International Publishing, Cham, pp 211%u2013221[2] Zhang C, Hu M, Di Maio F, et al (2022) An overview of the waste hierarchy framework for analyzing the circularity in construction and demolition waste management in Europe. Science of The Total Environment 803:149892. https://doi.org/10.1016/j.scitotenv.2021.149892[3] Scrivener KL, John VM, Gartner EM (2018) Eco-efficient cements: Potential economically viable solutions for a low-CO2 cement-based materials industry. Cement and Concrete Research 114:2%u201326. https://doi.org/10.1016/j.cemconres.2018.03.015[4] International Energy Agency (2019) Material efficiency in clean energy transitions. OECD[5] Monteiro PJM, Miller SA, Horvath A (2017) Towards sustainable concrete. Nature Mater 16:698%u2013699. https://doi.org/10.1038/nmat4930[6] Knoeri C, Sany%u00e9-Mengual E, Althaus H-J (2013) Comparative LCA of recycled and conventional concrete for structural applications. Int J Life Cycle Assess 18:909%u2013918. https://doi.org/10.1007/s11367-012-0544-2[7] K%u00fcpfer C, Bastien-Masse M, Fivet C (2023) Reuse of concrete components in new construction projects: Critical review of 77 circular precedents. Journal of Cleaner Production 383:135235. https://doi.org/10.1016/j.jclepro.2022.135235[8] Grangeot M, K%u00fcpfer C, Bastien Masse M, et al Prefabrication of structural walls from large rubble. 2026 (tba)[9] Grangeot M, Bastien-Masse M, Fivet C, Parascho S (2025) Large concrete rubble as a new structural construction material: opportunities and digital processes for load-bearing walls. Buildings Building Materials, and Repair&Renovation: https://doi.org/10.3390/buildings15091437[10] Grangeot M, Wang Q, Beyer K, et al (2024) Structural Concrete Rubble Arrangements: A Framework for Upcycling Demolition Waste into Slender Masonry Walls for Buildings. In: Eversmann P, Gengnagel C, Lienhard J, et al (eds) Scalable Disruptors. Springer Nature Switzerland, Cham, pp 15%u201327 https://doi.org/10.1007/978-3-031-68275-9_2[11] Grangeot M (2025) Re:bble 2D Scanner https://doi.org/10.5281/zenodo.18404477[12] Grangeot M, Auffret-Postel T, Parascho S, Fivet C (2025) New tectonics of concrete through rubble reuse. In: Structures and Architecture, 1st ed. CRC Press, London, pp 1185%u20131192 https://doi.org/10.1201/9781003658641-141