As stated by concrete sidewalk construction No, rebar is not required for a 4-inch slab of concrete on grade. A 4-inch-thick slab cast on the ground and in constant touch with it will float, with no need for rebar. On concrete that is 5 to 6 inches thick, rebar is recommended.
Is rebar required on a sidewalk?
Most sidewalks do not require rebar reinforcement.
Rebar may also be utilized in sidewalks that must endure the regular impact. The installation of rebar to general-purpose sidewalks is not beneficial. In fact, if your sidewalk requires repairs, utilizing rebar may cost you more in the long run.