Plumbing Leak Puzzle

[travelover]

Here is what is puzzling me; I have an upstairs bathroom with a shower with formed base and lead liner, a toilet and a sink, all original from 1966. Every couple of days, I will get about a cup of water leaking from the ceiling below. Then for several days nothing. My schedule is pretty consistent from day to day, so I'd think it would leak a little all the time rather than a gush occasionally.

About 6 months ago I found the copper drain pipe from the sink had developed a perforation. I cut that section out and replaced it with plastic and it has been fine since - I think.

Has anyone run into a similar intermittent leak problem like this?

Thanks in advance.

 

[inspectorD]

Uh- oh...sounds like you need to bite the bullet and get into the ceiling. It could be the water is building up somewhere in the ceiling or around that pan and finally reaches the top of the "DAM" and overflows. My money is on the shower pan leaking. It's past any lives of all the others I have changed.
Get into it because it will only get worse....fast.

 

[travelover]

Thanks, Inspector. I'm hoping you are wrong, but suspecting you are right.

Do you just cut out a large part of the ceiling under the bath to start or is there a more selective way to determine the source of the leak? My thinking is I'd like to keep the ceiling repair job as small as possible.