Hemp-lime biocomposite is the paradigm of regenerative architecture. It not only avoids polluting during production, but actively removes carbon dioxide from the atmosphere, storing it for centuries inside the walls of buildings.
The material is obtained by mixing hemp shiv (the fragmented woody core of the Cannabis sativa plant) with water and a lime-based binder. Hemp shiv is naturally rich in amorphous silica, which reacts chemically with the lime (pozzolanic reaction), petrifying the plant fibre. The result is a mineral sponge impervious to fungi, insects or rodents.
Unlike ordinary concrete, hemp biocomposite is not load-bearing (compressive strength ~ 1 MPa). Its real strength lies in dynamic hygrometry: the high porosity stores excess moisture (avoiding condensation) and releases it when the air becomes too dry, acting as a passive conditioner.
Standards
European and international references applicable.
Physical properties
Usage environment
Cast-in-place hemp biocomposite requires long drying times before finishes can be applied (lime or clay renders). In cold or damp climates, pre-dried factory blocks (prefabricated hemp blocks) are preferred to avoid construction delays.