The hybrid clay–timber floor system developed by Lehmit — a joint venture between Blumer Lehmann, Lehm Ton Erde, and gbd — is a bespoke innovation that combines prefabricated timber frames with compressed clay vaults. Locally harvested wood and clay excavated directly from the construction site were processed in a temporary field factory, reducing transport emissions and closing material cycles. The modules provide structural strength while offering thermal mass, humidity regulation, and inherent fire resistance, all with an embodied carbon footprint estimated at only a tenth of a conventional concrete slab. Designed for disassembly and reuse, the system embodies circular construction principles.
543 HORTUS, a project by Herzog & de Meuron, is the first building to implement this pioneering technology at scale.
