How to Make a Porch Slab

Dig 6 inches into the ground with your shovel. Remove the grass and dirt with your wheelbarrow and discard it into your compost pile. Smooth the area with your rake.

Build a frame around the outline of your slab. Drive 16d nails into the 2 inch by 12 inch boards to secure the form.

Dig holes for your piers with a round point shovel. Make each of the pier holes 18 inches wide and 36 inches deep. Place a pier every 3 feet along each axis to form a grid that will support the slab. Add 3 inches of gravel into the bottom of each pier hole.

Lay four pieces of your 12 inch rebar on the ground to form a square. Bind the corners of the square by wrapping each one with tie wire. Twist tie wire tight with your lineman's pliers. Build three of these squares for each pier hole.

Lay three of your rebar squares into the bottom of each pier hole. Drive a piece of your 48 inch pieces of rebar into each corner of the stack of squares with your sledgehammer. Drive each of the upright pieces of rebar so that its top is 1 inch below the top of the hole.

Slide the top square in your stack up until it it 12 inches from the top of the rebar stakes. Secure the square in place with a piece of tie wire at each corner. Secure the middle piece 12 inches below the first. Secure the final square 3 inches above the gravel base at the bottom of the pier hole. Add this structure in every pier hole.

Mix concrete and water in your wheelbarrow. Stir the mixture with your hoe, using enough water to create an oatmeal-like consistency. Shovel the concrete into each pier hole. Fill each hole to the top and let it dry for 72 hours before continuing.

Drive a series of 24 inch rebar stakes into the bottom of your slab area. Drive a stake every 4 feet each way to form a grid. Drive each stake so that its top is two inches below the surface of your form. Shovel 3 inches of gravel into the bottom of your slab excavation. Hold a 48-inch-long piece of rebar perpendicular between two stakes. Move the 48 inch piece so that it is 3 inches lower than the tops of the stakes. Secure the bar in place with tie wire. Connect each pair of stakes with perpendicular bars to form a horizontal grid.

Mix concrete in your wheelbarrow. Fill the form with concrete. Smooth the surface of your slab with a concrete float. Wait one hour. Float the slab again. Cover the slab with plastic sheeting. Wait 72 hours.

Remove the plastic sheeting and the forms. Let the concrete cure for another 72 hours before using the slab.