need help detecting the source of a bathroom ceiling leak
This morning, quite a bit of water came down through a tenant's bathroom ceiling. It seemed to coincide with the upstairs tenant, whose bathroom is directly above, taking a shower. There was no water on the upstairs bathroom floor.This means to me that there are two possibilities: either the bathtub drain pipe is leaking or the shower water is going through the tiled wall.
So I had them do a test. First, the bathtub faucet ran for 10 minutes. No leak.
Then the shower was pointed at one of the walls for 10 minutes. No leak.
Then the shower was pointed at the other wall for 10 minutes. No leak.
There was a leak in the same ceiling about a month ago, We did the test, and water leaked when the shower was pointed at one of the walls. I had it regouted, tested it again and the problem was solved. Now it's happened again but I can't recreate the leak to determine its source.
This is puzzling. Any ideas?