Do-It-Yourself Concrete Flatwork

Mark the perimeter of the concrete patio slab with a chalk line. Place wooden stakes 3 inches out diagonally away from each corner mark. This allows room for the form boards. Run strings between each corner stake.

Excavate the soil and sod to a depth of 5 inches inside the entire area using a shovel. If the patio is near your home, it should slope 1/4 inch per foot away from the house. Adjust the height of the strings to reflect the slope as needed. Tamp the ground down firmly with the back of the shove and spray the soil well with weed and vegetation killer to stop the growth of pesky weeds.

Pound wooden stakes into the ground at 3- to 4-foot intervals, working around the perimeter of the excavated area. The top of the stakes should be 1 inch higher than the excavated area.

Nail 2x6 form boards to the wooden stakes with double-headed nails, with the boards on the inside of the excavated area. The top of the stake must be even with the top of the form boards.

Spread a 2-inch-thick layer of gravel across the excavated area, tamping it down well with the back of the shovel.

Roll out strips of reinforcing mesh and cover the entire surface of the gravel. Flatten the mesh so it does not bow up. Place small rocks under the reinforcing mesh to raise it to the midway point of the 2x4 form boards.

Pour the concrete into the form boards until the area is full. Pull a long 2x4 across the top of the form boards to knock down excess concrete. Use a bull float to smooth the surface of the concrete by moving it back and forth in an arc shape. When water begins to bleed onto the surface, stop using the bull float.

Edge the slab by holding an edger flat against the surface with the front tilted slightly up while pushing forward. When pulling the edger back toward you, the back of the edger should be slightly tilted up.

Cut expansion joints at 4-foot intervals. Place a straight board across the concrete and drag a nail along the edge of the board. Each expansion joint should be one-quarter of the depth of the slab, so a 4-inch slab needs 1-inch-deep expansion joints.

Smooth the concrete further with a wooden or steel trowel, working in an arc motion. The more times you go over the concrete, the smoother it will be. However, you do not want it to be exceptionally smooth for an outdoor patio as it will be slick when it gets wet.