Problem
The slab is the easiest, cheapest, and most natural way to lay a ground floor.
Solution
Build a ground floor slab, raised slightly—six or nine inches above the ground—by first building a low perimeter wall around the building, tied into the column foundations, and then filling it with rubble, gravel, and concrete.
Related Patterns
… this pattern helps to complete Connection to the Earth (168), Efficient Structure (206), Columns at the Corners (212), and Root Foundations (214). It is a simple slab, which forms the ground floor of the building, ties the root foundations to one another, and also allows you to form simple strip foundations as part of the slab, to support the walls.
Finish the public areas of the floor in brick, or tile, or waxed and polished lightweight concrete, or even beaten earth; as for those areas which will be more private, build them one step up or one step down, with a lightweight concrete finish that can be felted and carpeted - Floor Surface (233).
Build the low wall which forms the edge of the ground floor slab out of brick, and tie it directly into all the terraces and paths around the building - Connection to the Earth (168), Soft Tile and Brick (248). If you are building on a steep sloped site, build part of the ground floor as a vaulted floor instead of excavating to form a slab - Floor-Ceiling Vaults (219) …
Alexander, Christopher. A Pattern Language: Towns, Buildings, Construction. Oxford University Press, 1977, p. 1009.