Possible Slab leak?

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Shadow_owl

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Since buying our house last year, water seems to be the thing that’s giving us the most difficulty.

Right now, there are two major issues we’re dealing with - one of them I’m asking about here, the other I’ll make a separate post for.

The biggest issue right now is determining if we might have a slab leak. There is water coming up between the floorboards in the kitchen. Some days it’s a lot some days it’s not so much.

Everything I’ve read in determining if you have a slab leak, points me to checking the meter when all water in the house is off. But I have a well/pump, not city water. So we do not have a meter to check.

How else would I go about checking for this?

Here’s some backstory that may or may not be helpful info:
1. a year ago lightning struck the incoming line outside the house, flooding the ground outside. It was repaired by a professional. No water ever leaked inside.
2. We’ve had issues with water under the kitchen sink. The dishwasher went bad. We took out the old one and a new one was installed by a professional. Before the new one was installed we found puddles of water sitting under the kitchen sink. When the new one was put in, he checked to make sure there were no leaks.
3. But shortly after we found a leak coming from the faucet itself (new/old, were not sure). We replaced the faucet ourselves. Problem seemed to clear up.
4. At some point after this, the water began appearing under one or two floorboards. I found no leaks, so I assumed that all the puddles from the kitchen sink (there was a lot of water under there) had soaked through the bottom of the sink, into the space below and was likely oozing out. After a while, the water disappeared, seeming to confirm my theory (it had finally dried up/evaporated).
5. Now the water is back, it’s coming up through the cracks in the majority of the kitchen floor boards. I didn’t notice any new puddles under the sink.
6. Also wanted to mention that the other day, the sink was clogged. While it was clogged, the water in the floor seemed to disappear. It returned after the clog was taken care of. Not sure if it’s a coincidence, or if perhaps the leak could be from the waste water line.

So all that said..... what’s the best way to determine where this water is coming from?
Please don’t say “call a professional”. I already know that, and probably will depending on what’s wrong.... but I want to see if we can at least determine the source of the problem ourselves.

Thanks in advance!
 
We don't usually see board on a slab. So you have a concrete slab with a wood floor in the kitchen?
If a water line is leaking it would leak less when the faucet is open. You have a lot going on but it does sound like it could be a drain line leak.
 
We don't usually see board on a slab. So you have a concrete slab with a wood floor in the kitchen?
If a water line is leaking it would leak less when the faucet is open. You have a lot going on but it does sound like it could be a drain line leak.
Yes, when I say floorboards, I’m referring to wood flooring. I’m sorry if I said that wrong.
 
Is this happening all the time or only periodically?
Aside from the day that the sink was clogged, it seems to be constant. But the amount of water oozing up through the flooring fluctuates. Some days it just comes up through 1 or 2 boards. Some days it’s coming up through a lot of them.
 
Unfortunately testing a waste system on a slab on grade dwelling is a real PITA.

As cumbersome as it may be, and short of removing the floor covering, stop using any water fed fixtures and appliances, in the kitchen and /or laundry, in the general proximity, for a couple of days.
 
Far more likely it's a supply line leak which is a very common issue with older slab houses.
If it was a drain line it would only show up inside the home if the drain line was completely stopped up outside the home, even then it's unlikely because there's no pressure..
If it's galvinized pipe it will leak at some point every time, even if it was not in a slab.
Even copper will leak if it's in direct contact with concrete.
All the Frank Loyyd Wright homes with supply's in the slabs all ended up leaking and being replaced with PEX.
 
To check if it is supply do you have a valve after the pressure tank to shut off the house? If so close the valve, wait 1/2 hour then listen real close as you turn it back on. If water has leaked out you will hear the pipes fill.
 
First of all, you will probably have to rip up the floor before too long as it will warp and also mildew from the moisture. You may get lucky, but I wouldn't bet on it.
You said you don't have a meter, but if you have a softener or filtration with a flow meter, you might be able to track it that way. The leak would have to be after the softener though, for that to work. A pool guy I know tests for leaks under concrete by pumping air into the water line and then listening for bubbles. Yes he can hear them right through the concrete. He also has a rig with a pressure gauge which he uses with compressed air. He adds air to the pipe and watches the gauge for a drop in pressure.
 
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