When they were built, some homes were constructed with an open space between the kitchen and living room, instead of being divided by a wall. While there are some advantages to this type of construction, such as making your home seem larger and allowing for freedom of movement between the rooms, the lack of a wall means that there is most likely no visual transition between the kitchen and living room. Building a half wall, or knee wall, can provide this transition while keeping the space open.
Measure and cut a pressure-treated 2-by-4 board to fit the length of the wall. This is called a sill plate, and is used to connect the frame of the half-wall to the floor.
Place the sill plate into position on the floor. Position the sill plate so one end butts up against the wall that is perpendicular to the half-wall. Nail the sill plate to the floor.
Measure and cut two 2-by-4 boards that match the length of the sill plate. These are the boards that will run across the top and bottom of the wall frame (the top and bottom plates).
Measure and cut 2-by-4 boards to be the studs for the wall. Cut the studs to the desired height, which is around 4 feet for a half-wall.
Nail a stud into each end of the bottom plate. These are the end studs.
Nail studs into the bottom plate between the two end studs. Generally, the studs should be no more than 16 inches apart, but follow local building codes when constructing the frame.
Nail the top plate to the tops of the studs.
Lift the assembled frame onto the sill plate. Check it for level (horizontally straight) and plumb (vertically straight). Nail the bottom plate to the sill plate, and the end stud into the wall.
Measure and cut sheets of drywall to fit both sides of the wall frame and the end stud that isn't nailed to the wall. When you cut the drywall, leave a 1/4-inch gap between the bottom of the sheet and the floor.
Attach the drywall to the frame by driving drywall screws through the drywall and into the studs every 6 inches. Drive the screws deep enough so the screw heads are slightly beneath the surface of the drywall.
Apply joint compound to the joints where the half-wall meets the existing wall. Place drywall tape over the joint compound, and press it into the joint compound with a putty knife. Allow it to set for the time specified on the packaging, then add another layer of joint compound and drywall tape.
Cover the corners of the outer end stud with a metal corner bead. This is an angled strip of metal that is placed over the exposed drywall corners and nailed to the end studs.
Cover the metal corner beads with joint compound. Smooth the compound with the putty knife to allow the joint compound to blend in.
Cover the drywall screws with putty. Sand down the putty and the spots where you applied the joint compound. Wipe the dust off of the walls with a rag.
Paint the drywall with primer and allow it to dry, then paint the wall with two coats of paint to match the other walls.
Measure and cut a ledge for the top of the half-wall. You can create a ledge yourself with a piece of hardwood such as poplar or maple, or purchase a ledge and cut it to size. If you make your own, sand the edges to give them a slight curve, then prime and paint the wood. Nail the ledge to the top of the half-wall.
Nail moulding to the base of the half-wall to hide the gap between the drywall and the floor.
Follow local building codes when constructing the half-wall.
Wear safety goggles when sawing the wood.