The Main House’s Ground Floor is Poured!
Concrete slabs are common foundation/floor systems in many parts of the world, particularly in warmer climates with soils that are stable.
Types of Slabs:
Monolithic Slabs
In a simple monolithic slab, the slab and the footing are one and the same, with the footing (at the perimeter of the slab and under any load -bearing walls) being “turned down” a lilttle deeper than the floor area.
The footing portion of the slab may or may not be reinforced with steel (rebars), depending on soil conditions and local code requirements.
The footing is set up and poured at the same time as the slab. This is done by digging the footing and forming the outside edge – typically with 2x lumber held in place with stakes and bracing until the concrete cures.
Slabs With foundation walls
In this type of slab, the edge of the slab is supported by the foundation wall. In the middle, it will rest directly on the ground.
With this type of slab, chances are there will some backfilling of dirt within the foundation walls to provide a supporting surface for the slab. This fill material should be good clean soil (no debris or vegetation) and compacted with a mechanical tamper to minimize settling away from the bottom of the slab. In areas where termites are a threat, get your pest control sub to treat the sand and soil under the slab for termites before laying the poly.
Information provided from Home Answers