Subfloor

A floor is the bottom surface of a room or vehicle. Floors vary from in a cave to many-layered surfaces modern technology. Floors may be stone, wood, bamboo, metal or any other material that can support the expected load.

The levels of a building are often referred to as floors, although a more proper term is storey.

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. As floors must meet many needs, some essential to safety, floors are built to strict building codes in some regions.

Where a special floor structure like a floating floor is laid upon another floor then both may be referred to as subfloors.

Special floor structures are used for a number of purposes:

Floor covering is a term to generically describe any finish material applied over a floor structure to provide a walking surface. Flooring is the general term for a permanent covering of a floor, or for the work of installing such a floor covering. Both terms are used interchangeably but floor covering refers more to loose-laid materials.

Materials almost always classified as floor covering include carpet, area rugs, and resilient flooring such as linoleum or vinyl flooring. Materials commonly called flooring include wood flooring, laminated wood, ceramic tile, stone, terrazzo, and various seamless chemical floor coatings.

The choice of material for floor covering is affected by factors such as cost, endurance, noise insulation, comfort and cleaning effort. Some types of flooring must not be installed below grade (lower than ground level), and laminate or hardwood should be avoided where there may be moisture or condensation.

The subfloor may be finished in a way that makes it usable without any extra work, see:

There are a number of special features that may be used to ornament a floor or perform a useful service. Examples include Floor medallions which provide a decorative centerpiece of a floor design, or Gratings used to drain water or to rub dirt off shoes.

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Wikipedia