I'm remodeling a house built in 1890. The second floor joists are 2x8, 16" OC over 12'. I just removed the cast iron tub out of the sagging bathroom (About 1 1/2' of sag). We want to put in tile and a claw foot. I have no problem removing the old joists. Will 2 - 2x8" be enough or should I go with 3 - 2x8's? Any help would be appreciated.

I am not an engineer but I think a laminated beam would be better.. just my thinking.. anybody else?

Keep the old joists and sister in new 2x8s next to them. Glue and screw the two joists together. That should be enough to keep the new floor from sagging. Do not reinstall any dimensional lumber for the floor sub. Use T&G plywood at least 3/4" glued and screwed and then a good backer like Hardiebacker or Wonderboard

Keep the old joists and sister in new 2x8s next to them. Glue and screw the two joists together. That should be enough to keep the new floor from sagging. Do not reinstall any dimensional lumber for the floor sub. Use T&G plywood at least 3/4" glued and screwed and then a good backer like Hardiebacker or Wonderboard

Ok - so I'll have 2 2x8's or a new one on each side giving me 3 2x8's? I think I have to remove the bathroom sub floor since it's level with the main floor on one side and then has about 1 1/2" slope where the tub was. We have 2 bedrooms with a bath between them. The bath was added when the outhouse came down. From what I can see - an oak floor was put in over 2x2's in the hall and front bedroom. The difference in height wasn't taken into consideration in the bath. Someone seemed to think the sub floor would "bend" or something. They have 2x4's & 2x6's sistered to the joists and shims between the bath subfloor and the joists that increase from 0" to a sideways 2x4 (1 1/2") under where the tub was. It's a real mess. So the floor in the back bedroom is fine, but about 1 1/2" below the rest of the floor which is pretty good considering it's from 1890.

I am suggesting adding one new 2x8 screwed and glued to the old 2x8. Yes you need to remove the old floor, thought you had planned on that all along based on your post. Now based on your more detailed description I'd tear the entire floor and old joist out and start from scratch.

Great - Thanks. I've been looking for you off and on all day. (I'm laid off). You'd really get a laugh if I could send pictures. To make things even worse, someone used concrete to level it.

Great - Thanks. I've been looking for you off and on all day. (I'm laid off). You'd really get a laugh if you could see it. To make things even worse, someone used concrete to level it. 2 009 shows where the transition in the floor was, 2nd from the left of the copper. 1 002 shows the "shims" and split joist. 5 011 shows my sistering job with 3/4" plywood. I'll be using hangers for the new joists.