In the process of renovating my master bath, I pulled out the vanity and discovered the water supply lines come up through the floor. The drain goes through the wall. The wall is a shared wall in a townhouse.

The vanity I bought has cutouts for the lines and drain in the back, not in the bottom. I'd this like to reroute the supply lines to come out of the wall rather than the floor. Is this a bad idea, given that it's a party wall?

  • 3
    you will need to get a permission to do any alterations inside shared walls
    – jsotola
    Commented Dec 31, 2019 at 3:58
  • 1
    How is this shared wall constructed? Not all shared walls really...permit utility runs within them....there's also the issue of making sure you don't screw up the fire rating on the wall! Commented Dec 31, 2019 at 4:31
  • 1
    The reason to avoid that (leaks) is precisely why you need permission. And w/o it on record, them cutting your pipes is your fault. I don't touch condo associations with a ten foot pole.
    – Mazura
    Commented May 31, 2020 at 11:17

2 Answers 2


Party walls between units must provide a certain sound control. If pipes are placed in the party walls, any noise from the pipes will only have about half the sound control between the pipes and either unit.


Waste water lines are louder than supply lines. So moving them into the wall should be fine. You also can isolate them but I don't think there is a need.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.