Slab On-Grade Foundations
SLAB ON GRADE FOUNDATIONS
Slab-on-grade foundations (also known as floating slab foundations) are a formal structural engineering best practice whereby forms are created on top of the ground by experienced concrete contractors. The Concrete is then poured into the mold at the desired PSI (pounds per square inch) such that no space exists between the ground and the structure being built. Concrete footings and slabs on grade typically require a concrete of 3,500 to 4,000 psi. The slab becomes the foundation for the home or building structure.
Slab Foundation Thickness
Typical Slab On Grade Thickness is 4”-6” thick. The thickness varies depending on the slab’s purpose. Patios, decks, and sidewalks are usually 4”. For heavier loads such as driveways, commercial or residential slabs, we usually see the thickness of 5”-6” . For larger trucks such as dumpster pads and 18-wheeler truck traffic, it is not uncommon to see the thickness at 7”-8”.
Slab Foundation Footings
Most foundations require footers that are poured at 24” below the final finish grade. Once the concrete footers are poured, the slab concrete is poured on top of the footers.