I demo'd a half wall (disregard errant cuts, I reinforced the stud from the other side) that separated our upstairs hallway from a stairs opening. We're having a metal railing installed, and I need to add blocking behind the drywall to reinforce this corner and receive the metal railing after drywalling.
My thought was to just double up 2x4s and screw them into the existing stud, with a few toe screws and lateral braces to fix it to the bottom plate and adjacent stud. My hurdle here where I'm starting to overcomplicate things, is the distance I need to extend is 3.5" and doubled up 2x4s would only extend it 3". Is there a best practice to extend this out the required distance and be sturdy enough to mount the railing to? I made 2" spacers but these cracked when I tested out screwing them in.... Would plywood work here?
