Plumbing in the Home/leak from tub to ceiling


QUESTION: Hello Dana,

I hope you can help me.  I have an upstairs shower/tub combo that is leaking onto the ceiling below.  I have attached a picture of the type of tub with Moen fixtures and a picture of the ceiling stain.
The building is a townhouse about 15 years old.  We have been living here about three years.  Six months or so after we moved in I noticed a small ceiling stain similar to the attached picture.  I had a plumber over doing some other work and asked him to investigate.  He said the problem was that the tub overflow had not been sealed when it was installed and he put on some clear silicone gel in the area.  We thought the problem had been resolved.
Then last week I was in the living room when my wife was taking a bath.  I heard a sound behind me and noticed a small drip coming from the same area in the ceiling.  The drip occurred as she was filling the tub, but seemed to subside after she was finished running the water.  The water level never went to the height of the overflow.  
The next day I took a shower and there was no drip.
I have two thoughts and would like your opinion.  It is drain related and only occurs when the tub is close to full or it is related to the diverter as the tub is filling.
What are your thoughts and how is the best way to confirm the problem?  I want to avoid any type of ceiling removal if possible.

Thank you for your time.



ANSWER: Hello Robert,
Based on your description, the likely candidate is the tub drain itself.  There is no way to verify or repair this without opening a ceiling and/or possibly the wall behind the tub.

The fact that it leaks when the tub is full and not when the shower is run points to the actual tub drain fitting in the bottom of the tub.  In order for the overflow to be a problem, the tub would need to be filled all the way up to the overflow opening and beyond.

Good Luck,

---------- FOLLOW-UP ----------


Thank you for your quick response.  I decided to take off the diverter
and fill the tub with water directly from the copper pipe.  I stood in the full tub to give extra weight pressure.  There was no ceiling leak.  I am thinking it is the O-ring in the diverter that's failing, so I bought a new diverter.  I filled the gap around the pipe where it comes into the tub with clear silicone.  I'm waiting for that to dry before I put on the new diverter.  Would it be possible for water to get back into the wall if the O-ring in the diverter failed?



It's possible that the diverter might leak back into the wall. should only be under pressure when using the shower.  When you pull up the diverter it blocks the water flow at the end of the spout and diverts it back up to the shower head.

Per what you said before, it only leaked when using the tub and not the shower.??  Strange.
Hopefully, the new diverter might do the trick.

Good Luck,

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Dana Bostick


Pretty much any residential plumbing questions. For "item specific" details such as a specific model of fixture, I will need to research and there may not be any useful information available. Note: I live and work in Southern California. We do not, as a rule, use hot water or steam heating systems, oil fired boilers or private water wells so my knowledge in those areas is pretty limited. There are others here on AllExerts that can probably answer those questions better.


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