Thickness carries the load, steel holds a cracked slab together, and the base is what the slab actually rests on. For North Texas flatwork the common reference points are 4 inches for cars and 5 to 6 inches for trucks, #3 rebar on chairs at about 18 inches, and a compacted stone or select-fill base over conditioned clay.
Updated November 10, 2026 · Metroplex Concrete & Stone
A 4-inch slab on a compacted base is the usual minimum for passenger vehicles; half-ton trucks, trailers and RVs push the recommendation to 5 or 6 inches, and edges are often thickened by an inch or two for 4 to 8 inches in from the perimeter. Going from 4 to 5 inches raises load capacity substantially for a modest increase in concrete cost, which is why a bidder who asks what you park is a bidder who is sizing the slab. City approaches are often thicker than the drive: Fort Worth requires 6 inches for the whole approach.
Source: ConcreteNetwork, how thick should a concrete driveway be
Reinforcement does not stop concrete from cracking; it keeps the pieces from separating and stepping once it does. Wire mesh is common at 4 to 5 inches and rebar at 5 inches and up. The spec you want on the bid is a bar size and spacing: Fort Worth's #3 at 18 inches on center both ways is a representative residential call.
Source: City of Fort Worth, Parkway Standards (driveway approaches and sidewalks)
Steel only works in the middle of the slab. Bars lying on the subgrade are in the wrong place; bars pulled up during the pour are inconsistent. Fort Worth requires 3 to 3½-inch chairs under the bars and the bars tied at every crossing. Ask for a photo of the steel on chairs before the truck arrives; it is the cheapest inspection you will ever get.
Source: City of Fort Worth, Parkway Standards (driveway approaches and sidewalks)
The base spreads loads, gives water somewhere to go, and separates the slab from soil that changes volume. A complete bid names the material (crushed stone or select fill), the depth, and compaction; Fort Worth's 95 percent of standard Proctor at optimum moisture is the kind of language to look for. Soft topsoil comes out first; a base placed over it is a base that settles.
Source: City of Fort Worth, Parkway Standards (driveway approaches and sidewalks)
The eastern half of the metro is Blackland Prairie, which Texas Parks & Wildlife describes as black, calcareous, heavy clay. It swells when wet and shrinks when dry, and a slab on it is lifted and dropped a little every season. The western counties sit on the Cross Timbers' sandy loam and the Grand Prairie's shallow limestone soils, which drain better but still move. In both, the base and the drainage around the slab are what keep it in one piece.
Source: Texas Parks & Wildlife, Blackland Prairie ecoregion
Thickness, steel and base control the forces; joints control where the crack goes. Spacing of about two times the thickness in feet is the Portland Cement Association's rule of thumb, and saw cuts should be made as soon as the concrete is hard enough not to ravel.
Source: Portland Cement Association, contraction/control joints in concrete flatwork
ACI 332, Code Requirements for Residential Concrete, covers slabs-on-ground, footings and foundation walls for one- and two-family dwellings, with chapters on slab thickness, vapor retarders and concrete cover. It is the document an engineer or inspector would turn to if a question about a residential slab went beyond the city's standard.
Source: ACI 332-20, Code Requirements for Residential Concrete (preview)
Thicker carries more, but a thicker slab on a bad base still cracks. Spend on the base first, then the thickness.
Either, in the middle of the slab. Rebar is the usual call at 5 inches and up.
Extra depth around the perimeter where the soil pulls away in a dry summer and the slab is least supported.
Tell us the job and where it is. One independent, insured North Texas contractor will look at it and send a written quote with thickness, steel, base, joints, finish, permits and dates on it.
Residential and commercial, in all eleven DFW counties. No price on this site, because the lot decides the price.
One vetted, insured North Texas contractor will call or text within one business day to set a time to look at it. You get a written quote with the full spec.