19 Non-metallic building materials, namely, wood and composite beams; concrete, concrete building elements, namely, trusses, floor and wall panels; shuttering, not of metal, for concrete; non-metal shutters for windows and other building openings; building panels, not of metal; tiles, not of metal, for building; building stone; doors not of metal; floor panels, ceiling panels, roofing panels and wall panels, all non-metal; door panels, door frames and sills, all not of metal; plate glass windows, for building; granite, gravel, limestone, clay sold in powdered form for use in the manufacture of wallboards and plastics, marble, rubble, namely, stones; Portland cement and slate; insulated glass for building; refractory construction materials, not of metal; ducts, not of metal, for ventilating and air-conditioning installations; works of art and monuments of stone, concrete or marble; non-metal mosaics for building; wainscotting, not of metal; parquet wood flooring; exterior blinds (outdoor), not of metal and not of textile; planks (wood for building); mantelpieces and chimneys, not of metal; wood pulp board for building, namely, plywood; works of stonemasonry, namely, decorative building facades and borders; scaffolding, not of metal; posts, not of metal; roofing, not of metal; roof coverings, not of metal; building cardboard, namely, sheathing board, roofing slates and gutters, not of metal; wood veneers; wood paneling; safety glass for building purposes; wall linings, not of metal, for building; wall claddings, not of metal, for building; window glass for building; windows, window frames and window shutters, not of metal; vinyl siding; non-metallic rigid pipes for building; asphalt, pitch and bitumen-based asphalt sealants; non-metallic transportable buildings; monuments, not of metal, namely, monuments of stone, concrete and marble