I know it’s standard practice to build temporary walls on either side of a load bearing wall for removal. In my situation the load bearing wall, the floor joists, and beam need to be replaced. I’m including a picture of a plan I’d like some insight and opinions on. I drew out my idea to support the ceiling load while providing enough space to work underneath to hopefully replace 8 foot sections at a time. There’s a mid span beam under the joists in place now but in order to build a temporary wall over the existing joists I’d either be cantilevered or have to build another support underneath just to transfer the load of the temporary wall down. Most of the roof load seems to go out to the exterior walls so I don’t think I’m supporting much more than just the weight of the ceiling and ceiling joists. This plan makes sense in my head barring the height of the 8′ jacks being a little sketchy if they weren’t plumb and the beam wide enough/supported well. Maybe even attach the beam to the ceiling joists themselves.

Also I plan on placing the support a little over 2′ back from the load bearing wall so when I frame it back I can fit a 4×8 sheet of subfloor underneath. Has anyone done it this way? Seems like it may be a PITA to keep it square to run out both ways but what would I do otherwise? frame it directly on top of the joists and just try to cut the subfloor as close to possible? Thanks in advance.