Help needed pinpoint shower leak!

[mikerc]

Hi-

After taking a shower I noticed water under tub in crawlspace.

After discovery, I dried ground and started testing but cant make the same puddle to occur again (of course!):
Ran tub thru spout only. No visible leak in crawlspace.
Ran shower thru head with nobody in it, no visible leak in crawlspace.
Caulk appears in good shape and there was no overflow or significant water on floor after shower.
Viewed drainpipes while running water and saw no moisture. Also did not see any moisture on the hot/cold copper pipes( no visible leak/puddle with shower off)
When shower/tub in off position, after 4 hours I see no visible puddle and only moisture where water exited/accumulated from behind wall and out a small hole that phone wiring exits.

Heres where I am confusing myself. When I found the puddle underneath, the only difference from any other time I shower was the diverter was left in the shower position overnight where normally it stays in the tub position. Perhaps unreleated, the valve/cartridge has leaked for a year into the tub from spout (I think I need new seats/springs) I wonder if the leaking cartridge with the diverter left in the shower position overnight caused the leak?

Unfortunetly a closer look at joint at head or the valve requires cutting of tile from front or drywall from back.

Any ideas or suggestion you can lend (besides call a plumber) ?

[kreemoweet]

A leaking caulk job frequently "appears" to be intact when it is not. Go around and try to flex tub/wall surfaces next to caulk joint and watch for tiny hairline cracks
to show up. Such little bitty areas of unadhered caulk can leak amazing amounts of water.

[Terry]

We sometimes see leaks from the tub spout. I would look further into that. My favorite spout replacement is made by Delta.

[mikerc]

It cant hurt to try to re-calk as suggested above. I would say there was about a pint of water on the ground... since I cant make it happen again with the tub running or the shower running (with nobody in it) it kinda suggests maybe its the calk or overflow that I didnt notice....??

We sometimes see leaks from the tub spout. I would look further into that. My favorite spout replacement is made by Delta.

If it was the spout, do you think it would be more likely to leak when the diverter is in the shower or tub position? FWIW, I replaced the spout for an unrelated reason/leak about a year ago and havent noticed anything until today.

Also for the heck of it, the faucet is a delta 1600 series circa mid 80's.

[nestork]

Mike:

I'm willing to bet dollars to donuts that you'll find the leak around the opening in the front wall for the T&S faucet handle(s) or tub spout. That's because when your grouting the tiling there, it's easiest to simply fill any gaps around the faucet handle(s) or tub spout with grout, but those gaps really should be filled with caulk instead. Any movement of the plumbing or wall will cause the grout in those gaps to crack and eventually come loose and fall out, leaving a hole for water to leak into the wall. You wanna have silicone caulk there instead.


You said:

Unfortunetly a closer look at joint at head or the valve requires cutting of tile from front or drywall from back.

Not necessarily. Nowadays you can buy a colour "snake scope" for well under $100. Just drill a 9/16 inch hole through the drywall behind the shower valve, and you'll be able to see where the water is leaking into the wall:

http://www.dhgate.com/wholesale/snake+scope+camera.html

The only problem with this endoscope is that it doesn't have it's own source of illumination, but if there's an attic above that bathroom, you can drill a larger hole in the top plate of that wall and lower small 12 volt light bulb or flash light into the wall.

[hj]

If you remove the round trim plate you can see the entire valve inside the wall. THe leak is probably from the tub's overflow opening. Spray water over it and see if the leak appears.