The foundation is the base of a structure and transfers weight loads from roof to the ground.
A solid, level foundation is critical to the success of the house. Foundation types include full basement (generally not seen in Florida), crawl space and slab. The two types of slab foundations are monolithic and stem wall. The house walls are constructed of concrete or cinder black while slabs are constructed of concrete. It is important to note that all concrete cracks are a result of the curing process. Only cracks as a result of displacement need to be checked for structural integrity.
In Florida the most common foundation is a slab foundation. A slab foundation is a flat piece of concrete placed on the ground which the house will sit on. The ground under the slab is the “pad” which is compacted prior to pouring the slab to ensure soundness of the slab.
There are two common forms of concrete slabs. Monolithic and Stem Wall.
A monolithic slab is a “one pour” process where as a stem wall is a tiered process. Both are considered a “Slab on Grade”. 
The concrete subcontractor stake and trenches the perimeter of the4 home. The trench is dug about 24 inches wide and 8 inches below the frost line. Approximately 8 inches of concrete is then placed in the trench. Three to five rows (i.e. courses) on concrete block are laid on top of the footing.
The top block is called a “shoe” block. It is a notched block designed to accept the concrete of the slab so that the slab will be supported by the walls, and the shoe block will act as a form to hold the concrete in place. Anchor bolts, used to attach the house frame to the slab, are3 installed in the shoe block at 6 foot intervals.
Grade beams are installed throughout the slab underneath all interior load bearing walls. Grade beams are usually 12” x 12” and often contain a few pieces of rebar. The plumbers will install sewer and water lines under the slab for the kitchen and all bathrooms. Wire mesh and rebar are typically laid throughout the slab.
The concrete is then placed 4-6 inches thick throughout the slab area. This concrete fills in the grade beams, covers the plumbing pipes, and ends on the shoe blocks.
A “Mono” slab is where the footings are poured at the same time as the slab. Sometimes referred to as “bell footing” the ditches (and pads) are dug around the parameter and under the bearing points… reinforcing steel is placed and it is all poured at one time, inside the form. Monolithic slabs are popular foundations because of their strength and longevity.
A “Stem wall” foundation (also known at T-Slab) is where the footings and or pads are poured then concrete blocks are laid up forming a wall to the slab grade. Then backfill is compacted inside the stem wall and the slap is poured on top. The stem wall acts as the form as the top course is usually finished with foundation blocks that create the form. Steel beams are also used in the footing ditch for this slab.
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