How to Install the Framing for a Cement Retaining Wall

Check local building codes prior to beginning retaining wall construction. Often, governing jurisdictions regulate multiple aspects of retaining wall construction, including the maximum height of a wall that can be built without professional engineering or approval.

Excavate the area for the wall and footing. The footing must extend below the depth of the frostline. Dig a trench wide enough to accommodate a footing that will have a width at least twice the width of the wall and a thickness of at least the wall width plus 6 to 8 inches of compacted base material.

Place 6 to 8 inches of coarse gravel or washed stone in the trench dug for the footing and compact it using a hand tamp or suitable machinery. Check to make sure that the gravel layer is roughly level and make adjustments as needed.

Measure and cut sections of 3/4-inch exterior plywood that reflect the height of the planned footing and cut several lengths of 2x4s that are several inches longer than this height to be used for staking and bracing.

Install the forms for the footings. Attach sections of plywood to each other using lengths of 2x4s and deck screws. Pound additional 2x4 stakes into the ground for support and place sections of 2x4s diagonally between the stakes and the ground for bracing.

Drill pairs of holes on opposite sides of the plywood forms near the top of the forms every few feet, then place wire through the holes so that it spans the width of the forms and holds them in place, keeping them from buckling. If an adequate number of 2x4s are used and attached solidly to the forms, this may not be necessary.

Place reinforcing steel bars, or rebar, in the space for the footing. Place horizontal sections of rebar that run the length of the footing every 12 inches and shorter pieces that span the width of the footing every 12 inches. Use wire ties to secure pieces to each other. Place pieces of rebar oriented vertically every 2 feet that extend from near the bottom of the footing to a few inches below where the top of the wall will reach.

Lubricate the interior of the form using form lubricant or used motor oil.

Pour the concrete for the footing. Use a wooden board or screed to make sure that the concrete is even and run a float over the surface to create a smooth finish. Once the concrete begins to set, cover it with plastic sheeting to allow it to cure properly. After about a day, remove the forms using a drill to detach the stakes and a hammer or pry bar to gently take the plywood forms off. After the concrete footing has cured adequately, the forms for the wall itself can be installed.

Cut sections of plywood that reflect the planned wall height and place them atop the footing where the wall will be installed. Use 2x4s and deck screws to attach adjacent boards.

Brace the forms. Every several feet along the length of the wall, attach 2x4s to the outside of the plywood form. Secure a section of 2x4 to the top of these boards to hold the shape at the top of the form and screw a board to the bottom of each 2x4 attached to the side of the plywood at a 90-degree angle. Attach this section to a stake pounded into the ground. Place an additional board between each side 2x4 and its stake. After the forms have been lubricated, the concrete can be poured and the wall finished as desired.