How to Build Concrete Riser Steps

Check local building codes for any regulations that pertain to step construction, tread size or other considerations. Incorporate any requirements into your project.

Plan the dimensions of the steps. Determine the total height of the steps that will be required and the desired riser size. Typically, a riser size of about 7 inches is ideal. Divide the total height by the riser height to calculate the number of treads required. Determine the desired tread length, typically about 12 inches, and multiply this by the number of required treads to realize the total length of the steps.

Prepare the site for the forms and concrete. Excavate the site to accommodate the total length and width of the steps to a depth of at least 8 inches.

Place 6 to 8 inches of coarse gravel in the excavated area and tamp it down to create a level, well-draining foundation for the steps.

Build the side forms for the steps. The side panels, which can be made from plywood, oriented strand board or stacked lumber, should be cut so that they are slightly longer and taller than the planned steps. Reinforce the side forms by nailing sections of two-by-fours to the outer side of each panel where the riser board will be placed. Additionally, attach lengths of two-by-fours to outer surface at the top, bottom and each end of the side panels. Make sure that the side forms are level and the bottom edges are entirely in contact with the gravel.

Install 2-by-8-inch boards between the side panels wherever risers will be to guide the front of each step. Use a level to make sure each board is level and pound nails through the boards to attach them to the reinforced side panels.

Brace the forms adequately. Place several two-by-fours or other lumber at an angle between the side panels and the ground. Pound stakes in the ground to brace the front and lowest riser board, and consider pounding stakes around the perimeter of the forms.

Spread or spray lubricant over the interior surfaces of the forms. This will allow easier and cleaner removal of the forms later.

Pour the concrete for the steps. Once enough concrete has been placed to build up each tread, smooth the surface of each tread with a small screed or trowel, using the board at the front of each tread. Use the trowel or screed as needed to fill in low spots or remove excess mortar from high areas. Run a float over the tread surface to create a smooth finish.

Run an edger over the front of each step.

Run a trowel or float and the edger over the treads again after several minutes once more moisture has exited the top of the treads to further smooth the surface.

Remove the boards from the front of the risers after the concrete has adequately set. Remove the nails holding the board to the side forms. Use a hammer to lightly tap the board off of the riser. If large chunks of concrete stick to the board, let the concrete cure a while longer before attempting to remove the boards.

Smooth the surface of the riser if removing the board left imperfections or spaces. Prepare a thin mixture of concrete and pack it into the front of the riser wherever needed, smoothing it with a float to create a uniform surface.

Remove the forms from the sides of the steps at least 24 hours after the concrete was poured. Remove the braces and tap on the back of the form with a hammer while lifting the boards off so they remain parallel to the sides.

Cover the concrete steps with plastic sheeting for a week to allow adequate curing. In extremely hot, dry weather, it may be necessary to mist the steps regularly throughout the curing period.