need slab leak assistance

[jayjohnson600]

Anyone have experience with slab leaks?

Looks like I've got one from the sound and the water meter spinning, plus the water bill was unusually high and the front door got tight like it was moving a little out of square. I've tried to do some locating. First guess by ear was near the kitchen.

I've put a shutoff valve on the supply side on top of the water heater, and I still have the meter spinning. So, my guess is that it's leaking somewhere between the main and the water heater. I have a second water heater on the other side of the house, but I don't hear anything in that area.

So, I made a fitting so that I can attach the air compressor to the end of the flexhose water line. I can put air to the piping going to the water main, or air going to the water heater if I needed to check that side. I'll get a tankfull of compressed air, pressurize the piping, then use an automotive stethescope to locate the floor spot where I can hear air escaping the loudest.

All the plumbers I've talked to say locating a slab leak takes experience, and/or special equipment and sensors. Then, it can still be tricky when you are near fixtures and walls.
The location spot may be a choice of one side of a wall of another.

I think that air testing might be a little better way of locating the leak versus listening for the water leaking past the pipe. Or easy enough to do both and confirm.

Anyone have experience with locating a slab leak and can help me pinpoint it?

[jayjohnson600]

Here's the fitting:

[black2002ls]

We have dealt with a few from work. We have had trouble on some locating them uaing professionals. How old is the home? If it is new enough to be a post tension cable slab, pay someone. If you bust a cable it can get VERY expensive to fix. It is something that I would pay to have repaired just from a recourse stand point. If they screw it up, they bought it and have to repair it again.

[jayjohnson600]

The home was built in 1987, and looks to be post tension cable.

I've called Estrella plumbing co and they will be coming out next week.
In the mean time I want to do some locating this weekend.

[FastFox]

Its usually the hot side leaking. Use a hand held thermometer gun to look for hot spots on the floor. I got mine at Harbor Freight for about $30.00. Works great on AC ducts and also on cars.

[kingjason]

I had one in my old house. It was between the main junction and the master bath on the hot side. I cut that MF off and pexed it, with shark bite fittings on both ends. Cost me around 80.00. and saved me about 2500 or so. My junction was in the side of the AC box and the other end was accessible in the garage so no real sheet rock damage. If I have a slab leak in this one I am having the whole house done. I put my water heater in that way also.

http://www.homedepot.com/b/Plumbing-Pipes-Fittings-Valves-PEX-Pipe-Fittings/N-5yc1vZbuty

[jayjohnson600]

Slab leak was found and fixed. I tailed them on the whole job, and learned quite a bit that I didn't know. If I run into a slab leak in the future, I'll be putting in the time for it.
They put the air pressure into the water lines(like I figured) and they used "Globe Geophones" for sound detection on the foundation. Then some strategic test holes looking for strong signs that helped to tighten the locating area. Tiles actually mde it a little more difficult, because the bedding under the tile was not consistant.

Cold side water line going to the garage sink was the problem. The leak was inside the pipe going through a foundation beam.
Had to open 2 holes and re-reoute under the beam with pex/sharkbites.
So, lost 8 tile squares in the process and fortunate that it wasn't under a wall, cabinets, something like that.

I was considering re-routing in the roof, but they wanted almost the same amount as fixing under the foundation. And if it was 5 feet closer to the outide wall I would have opted for tunneling. Just not quite lucky.

Ended up costing $1200(fixing) + $250(locating), plus the re-tile. The next lowest over-the-phone estimate was $1650 and the others were all above $2000.
There was one place that quoted using some epoxy injection on the circuit and didn't need to bust into the foundation, but they were quoting in the mid-$3000 range.

So, maybe I came out a little ahead in expense plus I was able to learn a couple of things to try it myself if I get another slab leak.

btw, one of the plumbers was a ringer for Edward Norton in American History X.
I called him out on it and he said that he does get that on occasion.


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