19 Profiles, not of metal, for the laying and finishing of flooring, walls, stairs and claddings; skirting and baseboards not of metal; non metallic membranes for buildings, namely, roofing membranes, waterproofing membranes for roofing, floors and walls, waterproof membranes for use as a floor underlayment; drainage installations, non-metallic, namely, non metallic drain pipes, non metallic drain bases, grates and covers, non metallic drains for use in construction of basement waterproofing systems; nonmetallic construction materials, namely, sloped drain bases and grates; building and construction materials and elements, namely, non metallic expansion joints for floors and walls, non metallic joint covers, non metallic drywall corner beads, non metallic corner joints and skirts for drywall, non metallic wall corner protectors, and listellos in the nature of trim to be inserted between tiles or wall boards; non-metal roof coverings; construction elements not made of metal, namely, supports for raised floors