The corner of an outside or interior two-by-four wall serves a dual function. When properly assembled, the corner supplies financing for stucco or siding, as well as drywall or paneling. When correctly installed, then the corner gives a sound structural connection at the junction of both walls. A do-it-yourselfer with basic carpentry skills can build and put in a two-by-four corner at a relatively short time using regular tools and fasteners.
Determine the overall height of this wall in the slab or subfloor into the peak of the double top plate. Deduct 1 1/2 inch to get the depth of the bottom plate — the sill plate — and 3 ins to your combined depth of the double top plates.
Mark three two-by-fours as studs to your corner assembly to length. Mark cutting lines across the face of this two-by-fours at every mark, using a builder’s square or speed square as a guide.
Put on safety glasses and then cut the corner studs at the squared marks, using a circular saw using a framing blade or a handsaw.
Place one of the studs apartment with a wide side facing upwards. Place another stud flat atop the stud and even the ends and sides of the two, using the square as a guide. Attach the top stud into the one below, using 16d framing nails at 16-inch periods from end to end. Instead, create the attachment with 16d nails along with a nail gun.
Repeat the previous step and attach the remaining corner stud apartment atop the next fireplace to complete the corner assembly.
Determine the place of this junction wall which forms an outside or inside corner. Put in the corner-stud assembly vertically between the sill plate and underside of the top plate with the borders of this two-by-fours at one side facing the direction of the sloping wall.
Expand the upper and lower faces of the meeting at the corresponding edges of the sill plate and top plate. Plumb the sides of the meeting just vertical, using a 4-foot level for a guide. Attach the lower end of this meeting at the sill plate using a set of 16d nails — toenails — at every side.
Work from a stepladder and attach the top plate into the top end of this corner-stud meeting with four nails, evenly spaced.