I am installing 36" doors in 2 walls to make a bathroom wheelchair accessible for my brother (replacing smaller doors). One is on a load-bearing wall. I am planning on putting in new headers that go all the way to the next set of studs (48" width), then double studding at the R.O. size.
My question is: Do I need to install temporary bracing, maybe 2x4's coming out diagonally into the room on both sides of the wall, while I cut out the old header and put in the new? This would prevent the wall from sagging, or is this unneeded? The room is on the ground floor of a 2 story.