How to Make a Concrete Slab Driveway

Level the soil. The soil must be solid enough to support the weight of the concrete. Grade the slab area to a level 3 1/2 inches below the level of the garage floor. The soil should be graded to allow about 1/4 inch to the foot (1 percent) fall away from the garage on the final concrete surface for water drainage. If there is no garage involved in your project set your form finish level to 3 1/2 inches above the finish grade level of the pad on which the drive is to be located.

Mark out the perimeter of the drive, including the side against the garage, using your twine and chalk. Using the square blade shovel, dig 12-inch by 6-inch footings at all edges of the slab to prevent edge breakage. Typical driveways from garage to street are 16-feet wide, to allow two-car parking.

Nail together 2-by-8 boards to run from the sidewalk to the garage slab. Line up the inside face of the form with your layout twine, which should be placed on batter board or offset stakes (see picture below). Drive 1-by-2 stakes vertically behind the form boards every 4 feet using the twine to keep the boards straight.

Set your layout twine with a 1 percent fall-away from the building, then nail your forms to the stakes. This will provide the necessary drainage.

Drive 1-by-2 stakes at a 45-degree angle behind the form boards every 4 feet using the twine to keep the boards straight. Place temporary kicker stakes inside the forms to keep the forms braced until the concrete is poured.

Place 1/2-inch rebar, top and bottom, in the perimeter footing hung off the form boards on tie wire. This rebar should be placed at all four sides of the driveway slab.

Cut and place 3/8-inch rebar at 24 inches on centers to form a steel mat in the driveway slab area. The mat should run at right angles to the garage door to start. Tie off the mat to the rebar in the footings to provide continuous reinforcement in the driveway slab.

Place 2-by-4 overheads to form bays which are 10 feet by 16 feet from one end of the drive to the other. Cut 2-by-4 screeds with 1-by-2 ears on each end of the screed to fit in each bay to level concrete as it is poured. The overheads or screeds are nailed to 1-by-2 stakes or set in special metal screed pins so that the bottom of the screeds is the actual finish level of the driveway.

Place the concrete from low end to high end. Premix and pumping is generally used by professional finishers. The concrete is pumped in to fill all bays equally and rodded off to achieve a roughly level finish surface. The overheads are pulled out and thrown aside. The concrete is tamped, allowed to cure, if necessary, and hand or machine finished with a steel trowel tor a smooth, slick finish.

Apply the final finish after the slab is level and smooth. The most common finish is a non-slip, which is applied with a stiff bristle broom. Expansion joints are scribed into the slab surface with V trowels and the job is completed.