slow leak from an upstairs

[AlexMercadoYce]

What are some ways to see if a slow leak from an upstairs bathroom is a plumbing problem, or a “too much splashing in the shower” problem?

[Jim Katen]

Stop splashing in the shower. 

[Jim Baird]

6 hours ago, Jim Katen said:

Stop splashing in the shower. 

Likely not just the splash but also the singing.

[Chad Fabry]

Take down the ceiling and watch the plumbing while someone takes a shower.

[smithcurtis]

You can test this easily enough by filling up the tub and letting it get high enough that it drains through the tub overflow drain. While it’s going through that overflow only - you look for leaks. If you find one then you know it’s the overflow connection.

If you don’t detect a leak in the overflow then you pull the drain plug and watch for a leak then. If no leak then look for floor compromises.