Load-bearing basement interior wall in poor condition

[MARTINOV]

The floor structure above the basement, how is it built? Hard to see in your picture. If it's a wooden joist floor, it's just a matter of lifting, but if you have a bathroom above with waterproofing, tiles, etc., you have to think carefully - it can turn out very wrong.

In this post, there is at least one picture of how I've done this. I've done it in two places in the house with this method and a couple of other places with wooden posts and beams. Where lifting was needed (where there was already a hole not properly reinforced), I've used a sturdy garage jack or alternatively posts and long levers. Note though that I haven't had anything sensitive above, just more wood - so I've been able to lift without risking problems.

[link]

Thank you very much for the response! Right behind the dresser where the clear "dip" is, there is a small guest toilet, and it is next to a bathroom, both bath + toilet are older and in quite poor condition. However, it's the only shower we have at the moment... The plan is to build a small bathroom in the basement and then later on merge the guest toilet + bathroom upstairs into a larger bathroom (as it was originally built before being divided into bath + guest toilet).

It's a wooden joist floor, but it must be lifted regardless, the question is just at what stage. Probably when the bathroom in the basement is finished so it can be used as a backup if the upper bathroom is ruined during the lifting process. But it feels a bit stressful to wait with this structural fault, it feels like you want to address it asap.

 

[MathiasS]

Thanks a lot for the answer! Right behind the bureau where the noticeable "dip" is, there's a small guest toilet that shares a wall with a bathroom. Both the bath + toilet are older and in quite poor condition. However, it's currently the only shower we have... The plan is to build a small bathroom in the basement and then eventually combine the guest toilet + bathroom upstairs into a larger bathroom (as it was originally built before being split into bath + guest toilet).

It is a wooden beam structure, but it will have to be lifted regardless, the question is just at what stage. Probably when the basement bathroom is finished so it can be used as backup if the upper bathroom goes down in connection with the lifting. But it feels a bit troublesome to wait with this structural issue, it feels like something you want to address asap.

If it’s a really old bathroom from the time before waterproofing etc., I assume there's a plastic mat in the shower – then I wouldn’t be too worried about lifting.

 

[cpalm]

It is wooden framework

Then at least it is concrete where there must be supports, etc.