Lowe's Home Improvement

Pour a Concrete Slab

Add extra charm and space to your patio by extending or creating a concrete slab. A concrete slab will give you extra room for cooking out on the grill or sitting and relaxing with friends and family.

pour a concrete slab

Tools & Materials

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Pour a Slab

Step 1

Sidewalks and patios should be at least 4 inches (100 millimeters) thick. For rectangular slabs, construct forms out of 2-inch-by-4-inch (50 millimeters by 100 millimeters) boards. For curved slabs, use 1⁄4-inch (6 millimeters) plywood for the forms.

Step 2

Dampen the forms and base thoroughly but don't leave puddles.

Step 3

Mix concrete mix, and shovel into the form to completely fill it at a uniform depth and approximately 1/2 inch (12 millimeters) above the form.

Step 4

After the concrete has been spread and compacted, strike off and level using a 2-inch-by-4-inch (50 millimeters by 100 millimeters) board. Move the edge of the board back and forth with a sawlike motion. Float the surface smooth using a wooden or metal float or darby.

Step 5

Cut the concrete away from the forms by running an edging tool or trowel along the forms to compact the slab edges. Cut 1-inch (25 millimeters) control joints into the slab every 6 to 8 feet (1.8 to 2.4 meters) using a grooving tool.

Step 6

For a smooth finish, use a steel trowel after the surface moisture has evaporated and the concrete has lost its sheen. A broom can be used for a more textured, skid-resistant finish.

Step 7

Cure the concrete according to instructions.