Water under marble tile

Today I was called to a clients house that cost about $5,000,000, he has a marble tile floor that is a slab on grade residence and there is discolarion to the sheen of the marble in a certain area. Nothing showed up on the thermal infrared camera, but using the protimeter survey master you can plainly see the high mositure where the discoloration is taking place. What I would like to know is what is the best way to determine exactly where the leak is taking place without having to rip up all the tile. Is there a tool out there? Once again it is in the supply line, because with all the water off in the house you can see the water meter move ever so slightly, but its dead center of his house and he is not a fan of removing the tile. Thanks in advance.


Any photos? Could it be surface water?

The pics don’t really show the sheen or lack of it…very slight, but evident none the less. It was not surface water. I really do think there is a small hole in the PEX plumbing located within the slab of the residence.

OUCH!!! That will cost someone.

This is all I could think of.

Would an IR camera help??

Without knowing the layout of the house its difficult to say but I have had success just abandoning lines and rerouting them overhead.


I have been successful in turning on the hot water side for about 15 - 20 (some times longer) minutes…mean while I am diagraming the home to determine the plumbing layout… so far it has worked for me. (even when it is a supply line, the heat from the hot water side should effect those water around same)

I would also expect a home that size would have drawings… I would locate them as well as trying to find out who the plumber / contractor was that installed same.

There are no instruments per se that will detect the origination…I went through this last year on several slabs including at a large apartment complex… the method I described above worked for me.

Let us know what you come up with…


Question for you IR guys.
Why cant you see the water ?

I assume it is a different temp from the surface.

Also Russell, how do you know it is a leak from dis-coloration evidence when something could have been splilled and you are getting trace readings.?

If problem is that marble and water are the same temp,would not heating the marble surface help ?

I wonder if ultra sonic could find a leak if the was one, I have some success with it in the past.

It would probably be better to cool the marble with a fan and due to convection the moisture would show with the IR. If the marble is heated the moisture will also heat and not really be distinct from the surrounding marble.


Ultrasound is one way to go. Those leak detectors work great! I had a cold water slab leak and could not find it with my IR called in an ultrasound and they found it in about 10 minutes (almost wanted to by one after that). Also removing one section of tile should not be that difficult. As was statde previously re-routing is also and option.

Just a few thoughts,


That’s what I thought as well. I’ve had plumbers perform ultrasonic leak detections and give an X marks the spot. I’ve done this with copper though…

Would be curious is pex irradiates sound like that of when a pin hole is present in copper.

I have been told,once marble discolors this way the stain will never go away even when dried. It may come to ripping out the marble anyway.

I had one a couple weeks ago and couldn’t find it with IR. Ultra sound should find it if the water supply line is leaking enough to see the meter moving. Around $1000 for a decent unit.

Just a few questions: How recent is this stain and how old is this floor? Does the stain come and go. Certain marbles if not installed with the correct floor mix or adhesives can cause staining over long periods. Could it be an area where ground water would be a problem?

improper testing procedures.

Sorry ,but what do you mean by that?

IR will not work through marble on slab without proper manipulation.

Is that temp or reflection problem?

I know Marble has a tendency to be cool.

The stain stays and is now permanent…I will go back on Friday. Thanks for all your help. People taking time out of their lives to help others…gotta love INACHI