Building and construction materials and elements, not of metal, namely, prefabricated non-metal buildings, non-metal door panels; doors, gates, windows, not of metal; transportable buildings, not of metal; structural elements, not of metal, namely, panels in the nature of building panels; casings, not of metal, for use in building or construction; cover panels, namely, construction panels in the nature of non-metal composite panels composed primarily of plastic, wood and press board; cover pa...