Roofing, not of metal; roofing, not of metal, incorporating photovoltaic cells; conservatories of non-metallic materials in the nature of prefabricated non-metal buildings; modular greenhouses, not of metal; transportable greenhouses, not of metal, for household use; transportable greenhouses, not of metal; pre-fabricated greenhouses, not of metal; building materials, not of metal, namely, waterproofing membranes for roofing, floors and walls