I have a very squeaky set of stairs going to the 2nd floor in my 1893 house. Not only are they noisy, but have settled/migrated enough that there are spaces as big as half an inch between the treads and risers. For a long time the gaps confused me but I've torn out the ceiling below and now see how things are framed up: there are two 2x stringers on 1/3 and 2/3 of the tread width, then the skirt boards act as stringers on the ends of the tread. There are actually grooves cut into the skirt board so that it both rests on top of the tread and supports it from below. This seems really weird to me. I plan to tear everything out, saving the existing 2x stringers, make 2 more identical stringers to replace the funky skirtboard/stringers that are in place now, and put everything back. The stairs are walnut and I think they're worth keeping and refinishing. My question is mostly about the skirt boards. I built a short flight a while back and I installed the skirt boards first, then cut my treads/risers to fit tight in between them. Reading online it looks like a lot of folk like to scribe the skirt boards in after, which seems like a lot more work and might be a real pain if things aren't perfectly straight like in an old house. Which way is best here? I'll also have to figure out walling - above the stairs is currently plaster/lath, and below the stairs is gutted. Also, refinish the treads/risers before installing, or wait till everything is in place? Any special glue/fasteners for making sure the stairs stay squeak-free? Thanks!

My wife and I recently purchased a 200+ year old timber-framed farmhouse. From the looks of things quite a bit of work had been done to reinforce the structure of the house (floor joist had been replaced, new footers, columns, beams in the basement), so I'm not extremely concerned about the structure being solid, but as you might imagine, literally nothing in the house is level/plumb/square. I don't expect it to ever be perfect, but as we start to remodel, I'd like to do what I can to begin righting some of the issues that it has. I've been having trouble finding good information on this old-style type of construction, which brings me here. Hopefully I can get some advice more specific to the challenges I'll likely face. The first major project we've planned that I'd like to get some preliminary advice on is a remodel of a small 3-piece bathroom on the first floor. We don't need to make any major plumbing or layout changes, but the major issue that it has is a significant list in the floor away from the exterior wall (only one side is along the exterior). The list causes the toilet to be slightly tilted to the left, so before I go about replacing anything, I'd like to try and fix this. I'm wondering what the best method would be. I've seen a bunch of methods for doing this, including shimming or sistering the joists, using a levelling compound, attempting to use jackposts. The current subfloor is tongue and groove floorboards. I'm not sure that sistering would work due to some of the plumbing that passes close to the joists underneath (there is a bathtub on one side of the bathroom that will be replaced). I'm not sure that jackposts would work, either (whoever did the previous work already placed a number of jackposts in the basement so I'm not sure I'd get a whole lot more movement in the floor). Fortunately, there is easy access underneath in the basement to do any work that needs to be done. I'd like to do this work myself if at all possible but I know there are possibly structural issues that would require professionals, particularly with a bathtub involved. Just looking for advice on what the best course of action would be. I likely won't be starting this project for a few months, but I'm trying to do as much planning ahead of time as possible, so any advice would be appreciated. Thanks!