Apparatus for draining roofs; non-metallic panelling for roof garden; interior walls of non-metallic materials; non-metallic dividing wall panels; non-metallic screen wall components; partition walls made of non-metallic materials; facade construction components of non-metallic materials; facade elements of non-metallic materials; facades of non-metallic materials; non-metallic building facade elements; non-metallic facade elements for buildings; non-metallic drainage apparatus; non-metallic drainage boards; non-metallic drainage products for use in building; rainwater drainage apparatus of plastic materials; non-metallic guttering for the collection of rainwater; non-metallic guttering for the dispersal of rainwater; non-metallic landscaping materials