Way OT, but youse guys are smart - slab leak

[zmudshark]

I luckily discovered a hot water line leak under the slab in our modest condo. It isn't too bad (no water visible, yet), and a guy is coming soon. I believe it is under tile in our second bath. The last bath I would spend money on.

Anyway, is there a way to seal a presumably copper hot water line under the slab without using a jackhammer/invasive surgery? I've heard of a process that injects some sort of epoxy/sealer into the line.

Anyone have experience?

In other news, there may be a Cinelli NSC be for sale, depending on the bill.:help:

[Tickdoc]

I luckily discovered a hot water line leak under the slab in our modest condo. It isn't too bad (no water visible, yet), and a guy is coming soon. I believe it is under tile in our second bath. The last bath I would spend money on.

Anyway, is there a way to seal a presumably copper hot water line under the slab without using a jackhammer/invasive surgery? I've heard of a process that injects some sort of epoxy/sealer into the line.

Anyone have experience?

In other news, there may be a Cinelli NSC be for sale, depending on the bill.:help:

I know of no quick fix for that. Lost a hot water heater last year, and spent all day sat w no water after a pinhole leak developed in a hot water line(copper) thankfully it was accessible and plumber was able to saw, and reattach.

Are you sure it is in the slab?

[zmudshark]

i know of no quick fix for that. Lost a hot water heater last year, and spent all day sat w no water after a pinhole leak developed in a hot water line(copper) thankfully it was accessible and plumber was able to saw, and reattach.

are you sure it is in the slab?95%

[AngryScientist]

I luckily discovered a hot water line leak under the slab in our modest condo. It isn't too bad (no water visible, yet),

i'm sure this is a stupid question, but how do you know there is a leak if there is no water visible ?

[pbarry]

Only way around this that is not invasive would be IF you've got a 1" soft copper or Pex line in there. Then a plumber might be able to fish through a 1/2" line inside the larger one. Or run a new line through the framing and abandon the leaky one. You'd still have sheetrock and maybe tile repair to complete in that scenario.

[thwart]

I could share a story about some minor basement flooding (that'll teach us to finish the basement :rolleyes:) 10 or 12 years ago due to a leak from the supply line coming from the street, 4 inches down deep in the slab.

Turns out it hadn't been plumbed properly when the house was built. Amazing what a tiny jet of water can do to a nice thick 3 inch copper pipe over a decade or two.

A jackhammer and sizable plumber's bill followed soon thereafter. But again, we had an obvious (and sizable) leak.

[zmudshark]

What's a Cinelli NSC worth?

[zmudshark]

i'm sure this is a stupid question, but how do you know there is a leak if there is no water visible ?The meter runs with all water off, water sounds in the room, hot floor, instant hot water in that room.

[unterhausen]

potable hot water line almost never goes under the slab. I would think it would be cheaper to go around it if some moron decided to do this. Radiant hot water heat being the exception, I think they usually have some kind of redundancy for this.

I am clearing stuff out of the basement and realized I had a plumbing leak for longer than I realized. There was a little discoloraton on the wall, but behind a cabinet I was throwing away, it was fuzzy with mold. Put a hold on my plans, that's for sure. Tearing out everything and I'm going to start over. Moral of the story: fix it now.

[cnighbor1]

there is the option of lining pipe with vinyl liner it is the want ads under plumbing
2nd option is reroute line over head and down
your talking sheet rock cut out about one 1' width I seen it done many times in remodels
Charles the architect

[zmudshark]

potable hot water line almost never goes under the slab. I would think it would be cheaper to go around it if some moron decided to do this. Radiant hot water heat being the exception, I think they usually have some kind of redundancy for this.

I am clearing stuff out of the basement and realized I had a plumbing leak for longer than I realized. There was a little discoloraton on the wall, but behind a cabinet I was throwing away, it was fuzzy with mold. Put a hold on my plans, that's for sure. Tearing out everything and I'm going to start over. Moral of the story: fix it now.This AZ, not normal US construction. hot water runs through/under the slab.

[zmudshark]

there is the option of lining pipe with vinyl liner it is the want ads under plumbing
2nd option is reroute line over head and down
your talking sheet rock cut out about one 1' width I seen it done many times in remodels
Charles the architectNot economically feasible with the construction I am dealing with.

[93legendti]

My in laws had that in their kitchen....insurance covered it...

Floor was really hot -unbearable without shoes if you stood in one place for too long...

[Tony]

there is the option of lining pipe with vinyl liner it is the want ads under plumbing
2nd option is reroute line over head and down
your talking sheet rock cut out about one 1' width I seen it done many times in remodels
Charles the architect

This

[BobO]

This AZ, not normal US construction. hot water runs through/under the slab.

Cold water under slab isn't uncommon in AZ. Hot water under slab is catastrophically stupid and rare. I've seen it a few times with lazy and/or incompetent builders. Thats just an exceptionally inefficient in floor heating system. To answer the initial question, no, you'd have to cut the slab. However, I wouldn't, I would abandon in place a re-route and insualte the HW line.

[lzuk]

If this is a common practice in Az the local plumbers will have a fix. I would try to reroute the line if I could. I would also use a heat gun to find the hot spot to isolate the leak. Isolation valves should also be a must on a part time residence.

[OtayBW]

There should be no corrosion problem with copper pipe buried in concrete; however, hot water pipe ususally needs to be wrapped with tape or insulation or some kind of sleeve to accommodate thermal expansion which could affects joints. Local building code should dictate this.

[GScot]

Abandon and reroute is a good plan. To pinpoint the leak rig up a stethoscope like listening tool. If you can't hear the water and you probably won't hooking compressed air to the line will make it easier to pinpoint. Cutting a small hole with a rental saw to inspect the leak is worthwhile as it should allow judgement of whether a damaged section is the problem and worth fixing or general corrosion and this was just the first place to let go.

[Birddog]

If there is access to the line in a wall on either side of the suspected leak, then a plumber can open the wall, cut the pipe and run a piece of PEX down through and up to the other access port. I've seen it done in 1/2 pipe. They use 3/8 PEX. We have both cold and hot water pipes under the slab in this region, it's SOP. This is only possible where the original pipe was flexible copper, they can't run the PEX through a soldered elbow, the turn is too tight.

[zmudshark]

If there is access to the line in a wall on either side of the suspected leak, then a plumber can open the wall, cut the pipe and run a piece of PEX down through and up to the other access port. I've seen it done in 1/2 pipe. They use 3/8 PEX. We have both cold and hot water pipes under the slab in this region, it's SOP. This is only possible where the original pipe was flexible copper, they can't run the PEX through a soldered elbow, the turn is too tight.That's what I will find out this afternoon. Stay tuned.

[jr59]

My bet is that it is under the slab.

All the fixes that I have ever heard of are stated here. None are that easy, with the slipping of a smaller flex(?) pipe thru being the least costly.

Good luck

[BobO]

There should be no corrosion problem with copper pipe buried in concrete; however, hot water pipe ususally needs to be wrapped with tape or insulation or some kind of sleeve to accommodate thermal expansion which could affects joints. Local building code should dictate this.

In the southwest corrosion of copper water pipe below slab is a big problem. The acidty and conductivity of the soil leads to a form of electromechanical galvanic action either between the soil and pipe or within the pipe itself. For the most part, we're going away from copper for this reason. What we're doing in existing conditions where changing out the piping is cost prohibitive is to install a sacrificial anonde.

http://atozleakdetection.com/preventing-corrosion-pinhole-leaks/

The anode will corrode rather than the piping and will add many years to the lifespan of the whole system.

[NHAero]

If you need to pinpoint the leak spot an infrared scanner may be a useful tool.
There's a long history of copper being corroded when cast in concrete - many houses with early hydronic radiant floors have this problem.

[OtayBW]

In the southwest corrosion of copper water pipe below slab is a big problem. The acidty and conductivity of the soil leads to a form of electromechanical galvanic action either between the soil and pipe or within the pipe itself. For the most part, we're going away from copper for this reason. What we're doing in existing conditions where changing out the piping is cost prohibitive is to install a sacrificial anonde.

http://atozleakdetection.com/preventing-corrosion-pinhole-leaks/

The anode will corrode rather than the piping and will add many years to the lifespan of the whole system.Sure, in soils or where water ingress can be a problem (or in otherwise acidic environments), this is true and cathodic protection systems are often used; however, the solution pH of even set concrete is extremely alkaline (pH>12) and galvanic corrosion of external copper surfaces buried in concrete is usually not an issue.

[BobO]

Sure, in soils or where water ingress can be a problem (or in otherwise acidic environments), this is true and cathodic protection systems are often used; however, the solution pH of even set concrete is extremely alkaline (pH>12) and galvanic corrosion of external copper surfaces buried in concrete is usually not an issue.

Water lines are rarely run "in" the concrete and merely pass through it as penetrations. But, you're right, the failure rarely occurs in the concrete.

[stansarch]

It's unclear on how it's known it is the actual HWH line... Can you describe the water accumulation and when it occurs? Like, is it sweating through tile, or pooling up in one certain spot after wiping down?

In general water issues aren't always straightforward and can also be a combination of things.

But if it is indeed HWH leaking in/under the slab - infrared and tear out is the most economical way. Tearing out concrete & tile stinks but really can be a fun D.I.Y. with friends since baths are generally smaller spaces than say, kitchen or living room.

There is no injection method allowed due to backflow issues that would taint public supply lines.

[Ken Robb]

In some condos the HOA is responsible for all plumbing so you ought to check with yours before spending your money. In other projects the HOA responsibility ends at the outer walls and in others at the inside surfaces of each unit.

[zmudshark]

To review/restate, I know there is a leak, even though there is no standing water (yet) because the water meter moves when all other water is off. The floor is warm to the touch, and I have instant hot water in that bathroom. A sound can also be heard. The HOA is NOT responsible for this type of leak, insurance may/may not cover it.

A leak detecting firm is coming out this afternoon. The plumber is coming out tomorrow (holiday today). IF the hot water if fed from the wall where my laundry is, we *may* be able to use PEX through the ceiling/walls, as Charles Nighbor said on page 1. Once we have the lines located, we will know more.

Thanks for all the suggestions. Our unit is not the first to have this problem. There are at least two others that I know of.

Building codes in 1980's PHX were lax at best, not enforced, at worst.

[zmudshark]

The cash hemorrhaging has begun. It is in fact a slab leak on the hot water side. The good (?) news is they will be able to PEX it through the walls/ceiling without removing the bathroom vanity/sink. Now I'm hoping the joists run in the right direction in the ceiling.

This bike may have to be sold, a Cinelli Nuovo Supercorsa (medium). I have no idea on what it is worth, because there are supposedly less than two dozen in North America.

https://lh3.googleusercontent.com/-1aQ02oLSsQc/Tup-KmN3vpI/AAAAAAAAKT0/ReJfiYdA40A/s800-Ic42/P1020291.JPG

Look for something in the classifieds after I get the bill for the whole project, assuming insurance doesn't cover the repairs. It is built slightly differently now, more Record/Chorus.

[sjpitts]

Been there, done that. I had to go through the same thing a couple of years ago. As I recall it cost me 150 or so to find the leak, and 900 or so to blast though the foundation, repair the leak, and pour new concrete. In the end I think I got off easy.

The scary part is that finding the leak is a bit of magic, and in some cases they miss. That can make what seems like an easy repair expensive, because the location of the leak really determines how much it can cost to put it back together. In my case the leak finder was only off by six inches or so, and the leak was under carpet in a closet. If it was under tile or under a fixture, that would have been a different story.

Long story short, you are probably being wise to go with the PEX.

[Birddog]

Building codes in 1980's PHX were lax at best, not enforced, at worst.
I feel for you, but the building codes and inspections are probably not the cause of the problem; it lasted 30 years or so. Best practices change over time as a result of problems like yours. Pex is the "wonder drug" of the plumbing world right now, and I've not heard of any horror stories re. it's use as yet, and it has been in use in Europe for thirty years.

The joys of 2nd home ownership are many, I know from my own experience. There is always something wearing and tearing on your domicile whether you are there or not. Good luck with the fix and hope your insurance covers it. Remember, your Homeowners typically will cover damage caused by the leak, but not the repairs to the leak itself. What size frame do you ride?

[Ken Robb]

I live in a condo complex and water pipe leaks in garage slabs in certain models are fairly common as they are 40 years old. Happily the repair is to abandon the leaky pipe in the slab and run a new line around the perimeter of the garage above grade and that is a much cheaper repair than digging up or patching the old line.

[pbarry]

I live in a condo complex and water pipe leaks in garage slabs in certain models are fairly common as they are 40 years old. Happily the repair is to abandon the leaky pipe in the slab and run a new line around the perimeter of the garage above grade and that is a much cheaper repair than digging up or patching the old line.

Above grade! Dang, you certainly have some advantages in that climate. :)

[Ken Robb]

Above grade! Dang, you certainly have some advantages in that climate. :)

Well, sometimes it gets down to 45F in the dead of Winter.

[Birddog]

So what is/was the resolution? Inquiring minds want to know.