Measure the available floor space and remove any carpeted floor covering before beginning your divider wall installation. Take up carpet along an interior stairway, for example, before securing the framing boards in place with 4-inch screws. Plan to secure board framing directly to the steps, versus nailing it, for maximum strength.
Design the depth of the wall. Use 2-by-6 inch boards instead of 2-by-4s as one option. Plan to build a waist-high wall 6 to 8 inches deep to provide stability for the structure. Design framework that consists of boards on 16-inch centers to form the studs for the wall construction.
Remove any stair railings or handrails. Pry loose any materials that are nailed in place with a crowbar but try to avoid damaging the steps or flooring material in the process.
Attach wood framing tightly so that it holds up well over time. Use 4-inch screws to secure studs to the framing with an electric screwdriver. Stabilize the framework so that the wall will accommodate constant use as an alternative to handrails. Cover the half wall with drywall, beadboard or another type of wall covering.
Nail up wood trim to provide protection for drywall or paneling on the new wall. Install baseboard material at floor level on interior spaces and wood trim to cap exposed corners of the wall. Nail wood trim over the finished drywall corners inside the home to further protect the wall in high-traffic areas.