A slab foundation means there is no crawl space underneath the property so the house rests directly on a thick layer of concrete.
In order to create the footings on a slab foundation trenches are dug on the outer perimeter then more concrete is poured on the exterior of the slab compared to the interior. This creates the intrinsic footings of the foundation.
Rebar adds strength and integrity to the slab foundation as well as helping prevent the slab from cracking.
Gravel is spread evenly throughout the base of the slab foundation in order to help reduce moisture.
Once excavation, back gravel, and rebar are completed the new concrete is poured. The new concrete is leveled once poured and left to set. Once the complete process is over you have achieved a slab foundation.