Flooring boards (non-metallic-); floors, not of metal; gratings, not of metal; latticework, none being of metal; stair-treads [steps], not of metal; staircases, not of metal; parts of street furniture, none being of metal; bridges, namely buildings, none being of metal; duckboards, not of metal; palings, not of metal; duckboards, not of metal; non-metallic insect screens, not of metal; pillars, not of metal; non-metallic pedestals, for building construction.