Need plumbing advice!!!

[Dora]

This past Sunday, my husband and I noticed that our pipes were making a noise like water was running somewhere. All faucets in the house were off, the toilet wasn't running, and all outside faucets were off. Still, the pipes were singing: it was very audible in the laundry room, kitchen, and the bathroom on the far end of the house. Our neighbor came over to vist, and even he asked if we had water running outside because he could hear it when he was standing in our kitchen.

We couldn't see any signs of water leakage outside our home, and there was no evidence of water leakage inside. Sunday and Monday were very wet days, so finding a slab leak outside would have been pretty tough. When husband turned off the water at the main valve, the sound stopped.

Monday night a plumber stopped by and told us that yep, sure 'nuff we had a water leak, and it was a hot water leak. Nope, he couldn't tell us where it was without using his supertechnogadget on his next visit for $220. But he suspected it was in the bathroom between the tub and the sink. He determined the problem was with a hot water pipe by shutting off the water heater, and thereby stopping the noise.

The weather has dried out here and there is STILL no sign of water leaking outside or inside our home. We're keeping the water heater turned off unless we need to run a sink of dishes or take a shower.

Is there anything besides a leak that can cause the pipes to make noise like this? And is there any way to repair a broken pipe without breaking up our slab foundation? (A contractor friend suggested rerouting the section of pipe in question through the attic.)

Thanks for any advice you have to offer!

[tsakshaug]

1. sounds like he is correct.

I never have owned a slab house for this reason.

You could re-route the pipes all you need is space to do it. It may be as expensive as whatever repair needs to be done, depending on the space and if you do get the correct pipe!

If you have access panels to your plumbing-behind the tub and the like, poke your head in, listen and look, see if you can figure out where the leak is that way

[Dora]

5. We were lucky

In this town, 75% of houses have foundation problems. I understand that we have a clay trough and lots of sliding around here in Central Texas. We were ecstatic to find our house with a solid slab foundation on firm ground and no signs of shifting. The house is 45 years old, and all walls, brickwork, drywall, etc is solid.

All access holes have been poked into. Dry dry dry behind the tub/shower, under the bathroom sink, under the kitchen sink, and behind the washer and dryer.

It's encouraging to know that re-routing is an option. I was worried about the pipes possibly freezing in the attic, but after my husband politely reminded me that it would be the HOT WATER pipes, I realized that it wouldn't be a problem.

Thanks for the reply.

[trotsky]

7. Hot water pipes can still freeze.

Doesn't take long for hot water sitting in a pipe to cool down, if you're not running that water frequently.

But I would imagine if they are good & wrapped it shouldn't be a problem - and if you'll be away from home during a cold spell, just shut off the hot water and drain the pipes.

[DebinTx]

10. I'm in Texas too

and a word of caution, your hot water pipes can burst after a freeze. I know because it happened to me. Pipes froze overnight and the next morning it burst when the hot water was turned on. It doesn't matter if the water is hot or cold, a frozen pipe will burst when the pressure builds up.

As a suggestion, I'd wrap those pipes with insulation. It's cheap and easy to do.

[tk2kewl]

2. i am not a plumber, but i would reroute the pipe if it is infact leaking

[phantom power]

3. you can certainly re-route thru the attic. The catch with that is,

you have to re-route all the hot-water supplies. If they can fix the leak directly under the slab, it *might* be cheaper.

This is important: check to make sure that it isn't the pressure-relief valve on the hot water tank. We went thru exactly the nightmare you are going thru, and later discovered that all we really needed to do was replace a $20 valve. I think the plumber was taking us for a ride on purpose. Basically, insurance fraud. They did $2000 worth of work, and billed the insurance company.

[TNDemo]

4. Only problem with attics

is that if you are in a cold climate the pipes can freeze in the winter and that is a big mess.

[phantom power]

9. Good point. I would only consider it in a southern climate.

Even then, I'd make sure they wrapped the pipe, and then laid the ceiling insulation on top of that.

[Dora]

6. Can you tell me more?

My brother said something similar last night. What happened in your situation?

[phantom power]

8. Well, our symptoms were exactly the same as yours

The sound of running water, and it stopped when the hot water was shut off. With slab construction, there are TWO possible causes. The first possibility is that there is a leak in your hot water line. The second possibility is that your pressure relief line also runs under your slab (as it did in our house).

To summarize: in our case, the pressure relief valve was busted, and it was sending water thru the pressure relief line, under the slab. This should have been an easy fix: replace the valve, end of problem. The plumber did far, far more than that. He was either insane (and I don't rule that out, he was one weird dude), or he did it on purpose, to bill extra work to the insurance company, or both.

A genuine leak in the hot water line is generally caused by slab settling. With copper piping, it takes a lot of settling, since copper is quite flexible. If you've got galvanized plumbing, it might be more brittle.

[Dora]

11. Super info!

Thanks so much! Our pressure relief line is copper, and it runs from the water heater straight out through an exterior wall (wood framing, brick veneer).

The plumber told us that our plumbing is galvanized "with some copper", but I think that much of it is copper. I say this because the original plumbing for the utility sink was copper. The house was built in 1958, and we can tell that the builder took the time to do some things right.

I'm going to take this info straight home!

[Dora]

12. I love DU!

Thank you to everyone who's given me their opinions and advice. You don't know how much it means to me!

Dora