How do i replace a rotten floor running under a stud wall which has electrical cable running through?

[Gary111]

I have a bathroom floor that is partially rotten, I guess I can slide some new flooring under the wall and leave the cables?
Ideally I would like to replace the wood in the wall that they run through, as it's a bit rotten at the bottom.
Not too bad though.

 

[blup]

Doesn't look great, maybe it looks worse than it is, but consider sistering the joists, ideally over the whole length but you could do the end section and drop them onto joist hangers. The section of ceiling next to the wall looks like lath and plaster that morphs into ceiling board so you could rip the former off and give yourself more working room.

Blup

 

[tell80]

OP,
Why not stand back and pic and post a larger bathroom context, & a detailed clear pic of the white stuff in the rot - with a better focus.
Does the white stuff go under the board on the left?
Whats on the other side of the wall - any signs of water penetration?
Any damage to the ceiling below?

 

[big-all]

i would also brush poke and prod to work out whats not nice but solid to oooo **** its knackered and soft