Plywood on a concrete garage floor?
Costs To Install Concrete Slab. Concrete slab installation costs a minimum of $5.35 per square foot for a 4" thickness, and as high as $10.55 per sq. ft. for a 6" slab with thicker edges, styrofoam beneath the slab, and wire mesh. Adding radiant heat, extra dirt work, or grading to the sub-base costs extra.