Fungus/mould or lichen can sometimes grow on a variety of building materials, including COLORBOND® steel, in tropical and temperate areas of Australia. Fungal growth occurs where the prevailing ‘local environment’ or an isolated ‘microenvironment’ are conducive. This fungal growth can be removed with the appropriate cleaning agents. For more information, please refer to Technical Bulletin TB-27 - Identification of fungus in the field and recommendations for its removal.