Although building concrete stairs is one of the more challenging exterior home improvement projects, however, carefully planned and executed, you will be left with stairs you can be proud of, and save upon labor costs as well. Follow these steps to successfully build your own concrete stairs.
Step 1: Determine Stair Location
Decide where you want to build the stairs so you can determine the appropriate stair rises (vertical height of each stair) and tread (each stairs horizontal surface).
Step 2: Calculate Stair Rise, Run and Footing
Use a measuring tape to measure the rise of the stairs—the distance from the edge of the porch or any upper part where the stairs are to be located down to the ground below. Note the measurement on paper.
Also measure the run of the stairs—the horizontal length from the foundation to where the stairs will start.
Demarcate the footing—a 6-inch deep bed of gravel and concrete that serves as a stable foundation for the stairs. it is essential for a safe and appropriate stair rise and run.
A riser height of 7 inches and tread width of 11 inches is sufficient to form safe and comfortable stairs.
Step 3: Create Forms
Use good quality ¾-inch plywood sheets to make forms for the stairs, or moulds into which concrete will be poured.
Measure and mark the length and height of the run and rise of stairs on both the sheets. Then use the measurements for tread and riser calculations to mark stairs. Carefully cut the form out.
Step 4: Install Forms
Carefully stand one of the forms on a side of the porch in the footing, making sure it is perpendicular to the structure of the building. Make sure it is level and plumb to the surrounding footing.
Install wooden stakes on the outside the form, spaced 10 inches apart. Use galvanized wood screws to attach the form to the stakes. Repeat with the other form placed on the other side.
Step 5: Cut and Insert Riser Forms
Use a handsaw to cut forms from lumber for the face of the risers. Make sure they are equal in height as the riser, and long enough to overlap the side forms. Use galvanized wood screws to attach them to both the side forms. You can attach sufficient bracing to the sides and center for extra support.
Coat the inside of the forms with lubricant so the concrete can release easily.
Step 6: Pour Concrete
Follow manufacturer’s instructions to mix concrete. Pour it into the lowest form first and spread it with a shovel. Tap it to remove any air bubbles, and allow it to set before proceeding to the upper layer. Repeat this procedure until you pour the top step.
Remove the riser steps, starting from the highest one, as soon as the concrete can hold its shape. Use a trowel to smooth out riser faces. Leave the concrete in the side forms for a week so it cures. Once cured, carefully remove the braces and side forms.