Using biochar as the raw material for thermal insulation allows for a temporary storage of atmospheric carbon in the building itself – in form of the insulation material – as well as providing the option for a long-term carbon storage after the material's use in the building. Because biochar is relatively inert, biochar-based thermal insulation materials with soil-compatible additives can be brought into the soil at the end of their life-time, where they act as soil enhancers and carbon sinks.

Biochar-based thermal insulation can be designed to have a competitive thermal performance, favourable fire properties – which allows the substitution of emission-heavy materials – and a significant carbon sink potential.

This work has been supported by the Minerva Foundation, the Klimafonds of Stadtwerk Winterthur, the Crescere Foundation, the Federal Office for the Environment and the Federal Office for Energy.