[Queso Bandit]

I have a localized area of dry rot under the bathroom. The water leak was repaired, but I'm curious the best way to replace the bad wood. The ends of 3-4 joists are in bad shape, as are a section of the bottom plate of the wall and the botton of some studs. The sill seems OK, but could probably use replacing to do it right.
Can I replace/sister 1 joist at a time without jacking? 2x6's They are 18" OC.
I was thinking of installing a temporary ledger on the good part of the studs to provide some support with a jack.
2 of the joists are so rotted at the end, they're hardly providing any support anyway, and the wall seems to be holding up fine. If I work in sections (maybe 2 joists at a time) could I avoid jacking?
Thanks, any advice is appreciated.
I'll try to post a pic...

 

[Bob Mariani]

yes, replacing a section at a time will work without jacking. Just use a sledge to force them into place.

 

[fixrite]

you could also pound in some blocking to the back of where your replacement joists are going this will give you the temporary support and will ease the installation of new joists so you will will not be beating the crap out of new joists as well.

cheers

 

[Queso Bandit]

Thanks for the comments.
Would you recommend replacing the joists or sistering all the way back to the girders (about 8') or would cutting off the rotten ends and sistering back 2' be OK?

 

[fixrite]

replacing all the way back is the right thing to do. It will not only give you the ability to level the complete floor, but ensure it is structurally sound.

cheers

 

[Queso Bandit]

arghh... more work. lol.
That's what I figured. Thanks!

 

[Scuba_Dave]

Is that a crawl space underneath?
If you are concerned about support now would be the time to install additional support under thern 2x6's. How far do they span? If there will be a tub I'd definitely put cement block under the 2x6's

 

[Queso Bandit]

Yep, it's a crawlspace. Easy access now with the floor out too.

The joists span about 8'. I was thinking of supporting the center of the span under the bathroom to beef it up. No tub, but I would hate to have issues with my new tile due to deflection.

For support I was thinking of running a 4x4 across the middle of the span, with 4x4 posts in those prefab concrete piers.

Is there a better way?

 

[Bob Mariani]

The rim joists (under the walls) can be cut back and only replace the rotted parts. The joists should be completely replaced but removing all bad sections and sistering with a full new one will also work.

 

[Scuba_Dave]

Actually if that is just dirt down there then you should put plastic down to prevent moisture from coming up thru the ground

 

[BigJim]

On one of my jobs back a few years, I had to replace a long section of mud seal, rim joist and bottom plate. We took a 2X12 and screwed it to the studs about 2 feet up on the inside and outside of the wall. We supported the 2X12 at both ends down to solid wood. After the 2X12s were supported at both ends we took the rotten wood out and replaced it, then took the 2X12s and supports off. We had no problems at all but you would have to replace your rotten wood a section at a time as I see from your photos.

Jim