How about black slate floors
The levels of a building are often referred to as floors and are described in the article storey. This paper describes the structure of black slate floors. Black slate floors typically consist of a subfloor for support and a floor covering used to give a good walking surface. In modern buildings the subfloor often has electrical wiring, plumbing, and other services built in. Because floors meet many needs, some essential to safety, floors are built to strict building codes in the first world. |