Concrete Driveway Thickness

Q. How thick should my concrete driveway be?

A. That depends on what kind of soil is being used under the concrete driveway. The soil should be gravel, with no rocks bigger than your fist for the base. The top 3-4 inches of soil should also be gravel with no rocks bigger than about 3/4 of an inch. This makes it easier to grade and rake out by hand.

The thickness of the gravel will depend on the climate where you live. Go at least as deep with the gravel as the frost line is in your area. If you don't have any freeze/thaw cycles, then 12 - 18 inches of gravel should suffice.

Compact the gravel in 8 - 10 inch lifts for a well compacted base that will not settle.

After properly preparing the sub-base, the thickness of the concrete driveway can be 5 inches thick for a residential home and 6 - 8 inches thick for a concrete driveway that will be used for business or commercial use.

I like to use 4000 psi air entrained concrete with fibermesh and tie a mat of rebar 18 inches on center both ways for added reinforcement.

Saw contraction joints about every 8 - 10 feet after the concrete hardens to help control any shrinkage cracking.

Then apply a concrete sealer to help cure and seal the concrete.