Pinhole leak under slab

[havasu]

I noticed that there was a 2' diameter wet spot on my carpeting today, which I know is in the general place where I have copper pipe running to my bathrooms, below the concrete slab. I pulled the carpet and pad, and the concrete looks dry, but is exactly where the idiot previous owner had done some pipe repair. The concrete is newer than the original, and I suspect I have a pinhole leak coming from the copper pipe, or where the idiot had made a previous connection.

My first thought was to start jacking out the concrete and patch the damn pipe myself, but my neighbor came over and warned me not to touch it, recommending I called my homeowner's insurance company. He said if I get in there and it turns out bigger than I hoped, then the insurance company refuse my claim since I've already been in the hole.

My neighbor had a similar leak and his insurance company paid out $3K for the repair. He said the plumber he used gets used here alot for this type of situation and they first place a leak detector to confirm the pipe is leaking from this specific spot. I would hate to dig a hole in the concrete only to find the leak is 3' to the left or the right.

What say the experts?

 

[johnjh2o]

Have the leak detection done.

 

[Matt30]

Seconded for leak detection. Dig the right spot the first time!

 

[havasu]

Well, after pulling the carpet and letting the entire area dry up, I tested the area today with a handheld moisture meter around the area and got < 5% where the wetness was located. I really don;t think I have a leak in the area, but rather the area under the thick plastic chair pad kept in the moisture in the carpeting from when I had a clogged A/C condensate drain line from 6 months ago, and it saturated the area near the chair pad was located. I've buttoned up everything and tucked the carpeting back to normal, and I will just watch the area closely for awhile. Here is a pic with an "x" where the center of the wet carpeting was located.

 

[Chris]

If it comes back I have a leak detector and thermal imaging camera we can take a look.

 

[frodo]

ditto on the testing first.

copper pipes are sleeved up thru the concrete, you very well can have a nail in your copper pipe
thru the sleeve at floor level.

the water runs down the sleeve under the slab. out the end of the sleeve. bubbles up thru the floor.

looks just like what you are showing.

 

[gargalaxy]

Start simple, check the leak detector dial in your water meter, if spinning then call for leak detector. Also a mechanic stethoscope will help to listen if leak (NOT to pinpoint but confirm).