Building materials comprising digestate

A process for manufacture of a building material comprising the steps of:

• mixing clay and/or sand with from 1% w/w to 30% w/w of a dewatered digestate, dried digestate, or digestate ash obtained from Municipal Solid Waste (MSW) on a dry weight basis,
• optionally adjusting the water content of the mixture,
• shaping the mixture,
• drying the shaped mixture, and
• optionally firing the shaped mixture,
• so as to form said building material;
• wherein the dewatered digestate, dried digestate, or digestate ash is obtained from MSW by a process comprising liquefaction of the organic fraction of MSW by addition of one or more enzymes to form a bioliquid, anaerobic digestion of the bioliquid, and isolation of dewatered digestate from the anaerobic digestion of the bioliquid, and optionally drying of the dewatered digestate to form dried digestate or optionally burning of the dewatered digestate or the dried digestate to form digestate ash.