Brunette Girl On The Floor

A ground-level floor can be an earthen floor made of soil, or be solid ground floors made of concrete slab. Floors above may be built on beams or joists or use structures like hollow core slabs.
Ground floor construction
Ground-level slab floors are prepared for pouring by grading the base material so that it is flat, and then spreading a layer of sand and gravel. A grid of rebar is usually added to reinforce the concrete, especially if it will be used structurally, i.e., to support part of the building.