University of Hertfordshire researchers have developed a building coating that uses bacteria to protect and self-repair against erosion.   The innovation is a pioneering new lime wash that contains non-pathogenic bacteria, which increases the amount of CO2 that a building surface can absorb through photosynthesis.  This, in turn, generates additional calcium carbonate that forms a more robust barrier against erosion, as well as encouraging self-repairing mechanisms.  Believed to be the first of its kind, a pre-production prototype is now being developed by the team, based on research by the Hatfield University’s zero carbon lab and the manufacturing expertise of UK Hempcrete, funded by the Arts and Humanities Research Council (AHRC) through the Design Exchange Partnership programme.