How to Pour a Cement Deck

Measuring and Marking

• Use a measuring tape to determine the basic dimensions of your concrete deck. Mark each corner with a stake, and use a chalk line or spray paint to draw the outline the perimeter of your proposed deck directly on the ground. If you're building a deck with an odd shape, use a garden hose to make the outline, and paint around it to make your template.

Digging and Leveling

• Start excavating the area based on the outline on the ground. Having one or two assistants helps. Start at the edges by driving a spade down along the lines and digging toward the center of the area. The excavation should be 4 inches deep, and use a carpenter level to ensure the ground is level throughout the hole. Use a tamping tool to make the soil perfectly flat.

Building a Form

• Every concrete pouring job requires a form to prevent the concrete from seeping into the surrounding soil. For a deck form, place stakes along the outside perimeter of the hole. Place 2-by-4 boards along the inside perimeter and secure them to the stakes with screws. Once the forms are established in the ground, spread form oil over them to help prevent the concrete from sticking as it cures.

Gravel and Mesh

• Gravel helps prevent the concrete from freezing while providing drainage into the soil to prevent the deck from becoming waterlogged and sinking. Pour gravel into the hole and spread it with a rake to create a layer of gravel 2 inches deep. Use a carpenter's level to make sure it is level. Lay concrete mesh over top of the gravel.

Mixing and Pouring the Concrete

• Plan to use about one 80-pound bag of concrete for every 2 square feet of space you cover. Mix the concrete as directed by the manufacturer. Spray the prepared area with a hose to dampen the gravel. Pour the concrete into the form starting at one corner, and spread it with a shovel. Push the concrete against the form and into the corners of the excavated area. Work with a partner to smooth the concrete with a length of 2-by-4 board by dragging the board across the top of the forms in a zigzag motion. When the form is filled and the top of the concrete is smooth, level it with a bull float, which can be rented from most hardware and home improvement stores. Lightly mist the concrete with water, cover it with plastic sheeting and allow it to dry for three days. Drying may take longer in colder weather. Once the deck is dry, it may be used immediately, although sealing it with exterior concrete sealer can provide added protection.