When you’re framing a wall, inside corners can through a curve at you. (I know, we’re stretching it, but couldn’t resist.) In addition to building a strong wall, you need to provide a nailing surface for the drywall or other wall finish.
If you simply erect one wall, and then erect the next one perpendicular to it, you won’t have a place to nail.
Over the years, carpenters have come to rely on a variety of methods.
The three-stud corner
This provides a very sturdy corner, and it leaves enough of an overhang (when dealing with 2x4s) for a drywall nailer. But it has a couple of drawbacks. For exterior walls, it doesn’t allow for insulation in the corner. And if you have to run wires through it, drilling is going to be a big â€“ and a tricky â€“ task.
By sandwiching short lengths of blocking between two studs, you allow a gap for wiring and for some insulation. Butâ€¦ is this really necessary?
The two-stud return
This method works for whatever dimension lumber you’re working with, allows for a nailer, and allows for some insulation.