I'm trying to determine if I can make some changes to my house's interior walls without making changes or additions to the underlying beam/pier/foundation structure. I have attached a drawing of the existing beam/pier/wall layout and I have marked the changes I want to make as A-E on the drawing (note that the description of the specifics of A-E is on the lower right of the drawing).
To summarize the house in text (also noted on drawing):
- Built 1924
- Single story with steep gable roof
- 4x4 beams on 4x4 posts to piers
- Continuous footings under exterior walls (raised foundation)
- 2x6 floor joists
- 2x4 exterior and interior walls (stucco exterior)
- 2x4 ceiling joists (for the most part; deviations mentioned on drawing) with 1x4 "cross" braces in the attic above (I'm sure there's a name for these, but I don't know what they're called)
- 2x4 rafters
- Lath and plaster walls and ceilings
Changes I'm looking to make (also noted on drawing):
Item A: open the wall from the current 30" doorway to a 7' opening. This wall is not load bearing (it is parallel to ceiling joists and roof rafters), is not directly on top of a beam and is not connected to the roof except where it meets the adjacent walls. My concern is that this is a shear wall since it's lath and plaster.
Item B: move the wall 2 feet. There is no overlap of ceiling joists atop this wall though I'm guessing it helps ease the span of the kitchen ceiling since the existing 2x4's are not to code across the existing 11-foot span. Will likely have to upgrade these joists to 2x6's or maybe even 2x8's based on what I'm seeing in the span table for ceiling joists if I move the wall.
Item C: load-bearing wall with ceiling joists overlapping on top. Wall is currently roughly atop the beam/piers below. I want to move it 2 feet away from the beam below. Guessing this is not possible without potentially putting a new beam and piers below the new location of the wall, but maybe it's possible to cantilever (if that's even the right word)?
Item D: want to add a new wall here to create a hallway. It would not be directly above a beam, though the intent is not to have this be load bearing
Item E: similar to C with ceiling joists overlapping on top. However, this wall is currently not above a beam/piers. It would actually be moved 2 feet closer to a beam with the change I want to make.
Any feedback on items A-E would be greatly appreciated.