Can I Attach Stair Stringers To Interior Drywall or Plaster?
You can attach a stair stringer to a
wall that has already been drywall or plastered... In most cases.
As a matter of fact, if you installed your stairway after the walls had been framed and drywalled, it could provide you with a little extra fire protection.
This wouldn't be a preferred method of construction, but if you had an existing building that needed a new stairway, then feel free to attach it with nails, screws, bolts and brackets to the existing wall.
However, there is one drawback to working with existing walls that have already been covered with drywall or plaster and it would have something to do with the electrical wires, plumbing pipes, heating ducts or structural building components.
The picture above provides you with an excellent example of what I'm talking about. The black arrow is pointing to a live electrical wire and the white arrows pointing to the spot where the wire goes through the wall stud framing and was damaged, the moment I put a screw into this metal bracket.
The last thing you would want to do, would be to drive a large nail or screw into a pressurized water pipe or electrical wire that's hot or active.
If you don't know what's behind the wall, then it wouldn't be a bad idea to find out what's inside the wall or avoid attaching the stairway to the wall entirely.