Non-metallic building materials, namely, partitions, boards, panels, frame-work, pipes, tubes, struts and beams of non-metal; flooring structural supports of non-metal being construction elements; non-metallic rigid pipes, rigid tubes and beams for floor construction purposes; bridging supports of non-metal, plastics or composites being construction elements; pillars or support legs and/ or feet of plastics or composites being construction elements for construction of floors; loft access hatc...