A large part of an old house I’ll be working on is rotted due to water damage where an old porch used to connect to the house. The rim joist, sheathing, and subfloor are super rotted. What is the best way to get a new subfloor under the wall? I was thinking place a few jacks 4 or 5 feet back from the wall inside and jack it up enough just to cut any nails connecting the subfloor/joists and hte wall and then raise the wall off the subfloor. Then I would put in a 3 or 4 foot wide section of subflooring under the wall and lower it back down. Then I would be free to proceed as normal with the flooring. Does this sound like a good idea? A harder problem will probably be the interior walls that also have rotted subflooring under them. Typically when redoing an old bathroom, I would just chisel and remove the floor right up to the bottom plate. But with this place, the subflooring is so shot it will need to be completely removed on both sides of the wall, and underneath it. I’m not sure how to proceed. Ideas?
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Replies
You need to open the wall and attach a ledger board to the studs to jackup and support the wall while you work on the subfloor and joist.
You don't have to lift the wall much but you need to support it.
As Bill said, you probably want to attach a ledger to the wall, bolted to the studs. You wouldn't necessarily have to strip the wall to do this, but you would probably want to chop holes in the wall every 4 feet or so to run beams through (under the ledger), to give you something to jack on.
Jacked this way you can replace the rim joist at the same time, so long as your jacks aren't bearing on joists attached to the rim.
Use the same basic idea on interior walls -- you only need 1/2" or so.