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Title of Question:

Slab And/Or Toilet Seal Leak


Name: Nicolas Dzepina  City:

Question: What are the symptoms of a slab leak versus a toilet leak between the slab and the tiles? The plumber with his slab leak detector says he is sure at 90% it is a slab leak... because there is a hissing noise when you listen to the feeding pipe...but that noise could come from the water heater when on? I am not convince it is a slab leak since in addition he does know for sure which line is the feeding one. He claims he has to cap it to find out! Three months ago I noticed two black moldy spots on one of the bedroom baseboard drywall which separate the bathroom... with no sign of moisture anywhere around on each side. Two weeks ago the carpet was wet alongside the baseboard where the manifold pipes shaped as a ( m ) are located , and I could see ON and OFF a small water thread coming out underneath that baseboard...but not around the 3 manifold pipes going into the slab once I opened the wall. That water thread underneath the baseboard became more prominent after repeatedly playing with the toilet flushing...then mysteriously disappeared after I shut off the toilet tank valve...and removed the baseboard. After leaving all the valves on, and normally using that toilet, two black thumbs like imprint (mold) appeared 3 days later near the toilet seat post on one of the tile infront of the manifold pipes, with some sign of moisture on that same tile. I have since shut off that valve but kept the main water line on...and nothing is happening...that is why I think (rightly or wrongly0 it might be a broken seal between the slab and the tile. The plumber claim it is a pinhole leak that might have been plugged up with sediments? I would appreciate your expertise on this before embarking on expenses I might not need...? Today I turned on the toilet tank valve and will use that bathroom normally to see what will happened. If new moldy spots reappear then does that mean for sure it is a toilet seal leak between the slab and the tiles? Thank you. nicolasdzepina@hotmail.com


Name: homebild | Date: August 25, 2004, 18:45
Answer: If you hear 'hissing' and the leak dries up when the toilet valve is shut off, it is likely NOT a toilet seal leak. Sounds more like a toilet supply leak and the leak may be in the wall or floor.


Name: Nicolas Dzepina | Date: August 26, 2004, 12:38
Answer: Thank you homebild. May I ask you a clarification: By toilet valve do you mean the knob that is used to let and or prevent the water to enter the toilet tank. That's the one I am refering to and NOT the main water line valve line. If I have a toilet seal leak where would I see the water leaking? Thanks again