Slab leak in hot water

[noonehere]

My house is on a slab in metro Atlanta. The water supply comes in on the left side of the house, runs under the house to the right side where the water heater is, then the hot water goes back to the left side, where the powder room is downstairs. Two baths upstairs above it. And the kitchen sink in the middle.

I had a slab leak repaired in the powder room (hot water) about 10-12 years ago.

I had another repaired right under where the hot water from the heater goes under the slab in the utility room (actually, it was probably a foot or so beyond the wall in the den, but the plumber managed to fix it.).

Now, 2 months later, another leak. I'm "hoping" it is the same spot the plumber fixed last time. I stuck a Q-tip down along the pipe through the concrete, and it came out a little damp, though not wet.

I am considering long term alternatives, such as rerouting the hot water return up the attic and downstairs. (maybe I should do cold water while I'm at it)

1) Has anyone had experience with this kind of problem?

2) Is it safe to do this through the attic, that is, is there a potential for freezing, or would proper insulation or using that plastic pipe (PEX???) prevent it?

3) Any ideas on the reasonable cost range?

4) Would this be "code" in Cobb County, GA?

Thanks

[hallerb]

yeah PEX the entire thing, hot water in attic fine, cold water in atlanta will come out hot after spending time in attic

copper corrodes and leaks in concrete it will only get worse.

might put a point of use electric tank at the powder room if its the ONLY hot water used in that area

[noonehere]

Well, when the plumber jackhammered the slab at the old repair site in the utility room next to the heater, it was leaking, but a few inches beyond his repair. He had to go around the other side of the wall to the den, pull up the rug, and drill another hole there. The pipe was really corroded and full of pinhole leaks. He managed to patch it for now. Cost was $800 (discount because I paid $1400 the first time).

He said the copper pipe was Type M stick copper, vs. Type L which should have been used. The plumber and the owner said they never saw such bad pipe. On the first "dig", he found a scrap piece of rebar against the pipe. Maybe that was a factor.

Anyway, neither they nor I think this is a long term fix. They suggest rerouting the pipe. Since the heater is on the far side of the house from the supply line AND the heater (poor house design), the plumber recommends rerouting both hot and cold. He suggests rerouting underground around the back of the house. So they will still be buried, but at least not under the slab. total cost estimate is $6400, less $500 credit (from last repair) and $300 off if they can easily tap into all the other plumbing. It would not be exactly "direct" across the back, as I'll need to add on s few feet around the patio and deck.

Here is what is required:

1) Move my service from the front left of the house to the back left 2) Run about 60 ft (???) of L coppersupply line to back right of house to heater in utility room 3) Run same L copper supply from utility room to back left 4) Hot and cold into powder room to tie into trunk if possible. Not quite sure how difficult this will be until they cut sheet rock. We really don't know yet if the kitchen sink (middle of house) and upstairs 2 baths can be accessed here (hope so) 5) 2 new hose bibbs 6) Cold water line from utility room across garage ceiling and into kitchen for refrig. ice maker

I will need to patch the sheet rock.

Currently it takes a minute or 2 to get hot water. It sill be a little longer, adding the additional few feet to go outside around the patio - maybe 15 or 20 ft longer. Still a foot underground, so not much different from being under the slab.

Any comments?

[hallerb]

get some more estimates PEX the entire mess. doesnt matter what kind of copper pipe was originally used bury in coincrete it will rot and leak.

since plumber said wrong type he isnt to be trusted.

get more estimates

[hallerb]

could add at little expense recurilatring pump to have hot water all the time at bathroom. either manually operated push button a few minutes later get shower water nice and hot, or a motion detector to do essentially the same thing .

a point of use electric tank at the sink might be a nice add, just push button when needing shower, sink always ready to go

[hallerb]

USE PEX its way cheaper and easier to work with, tolerates minor freezes, and is self insulating. so that long run of hot water will be mch hotter when it finally arrives.

get more prices i bet with pex and perhaps you do the digging the long run you can do it for 1/2 the estimate, and have a better job too

100 feet of pex 34 bucks

[noonehere]

Sorry if this is a duplicate, my last post didn't take.

The plumber showed me what he pulled out and said it wasn't type L. He showed me Type L and told me it had a thicker wall. The old stuff appeared to be thinner. So I don't know if he was snowing me.

I was also considering either 1) building an extention of the laundry room and moving my water heater over there or 2) getting a tankless heater over ther (inside or outside unit). It would mean eliminating those two runs of waterline, though I'd need to run a gas line about

20 ft from the meter. These could be cheaper in the long run.

The plumber and owner don't seem to like PEX. Is it harder to deal with? I mean, this is not a small outfit.

[Stubby]

About 5 years ago, I started getting pinhole leaks from the heating runs in the slab. They kept getting worse so I abandonned the slab system and installed baseboard forced hot water. At the same time, I replaced the fresh water runs. I used heavy copper tubing, but if I did it today, I would strongly consider PEX. The real plumbers I've talked to are skeptical saying we don't know how long PEX will last. Contractors seem to want to do PEX because it is cheap and easy.

Note: The problem with any of these schemes is getting passed doors and sliders. I chose to chissel a channel in the slab. Going up to the attic would risk freezing and was just too complicated.

Good luck.