Under slab leak. Retrofit recommendations?

We had a domestic water leak about 5 years ago and Glen Wagner came out from Anderson Heating (an advertiser on this site) and jackhammered it out and replaced the part of the pipe that corroded. He was neat and efficient and it was done pretty quickly considering the work that had to be done. I didn't reroute the domestic water on the roof and haven't had a problem since.

My neighbor had a leak a year ago and fixed it then had another a few months later and threw in the towel and put it on the roof. There are some who would prefer to just keep fixing the slab leaks but it depends on your tolerance. You will need to keep a close eye on your water useage and occasionally I make sure and turn off all the water in my house and stare at the outdoor water meter. If it moves (even ever so slightly), it may indicate a leak. Glen showed me what to look for. I also keep an eye on my water useage every month to make sure it doesn't look out of the ordinary.

Good luck, Lynn

Thanks for the quick response, I was going to call them to take a look.
The main problem is that the kitchen tiles in my kitchen are warm so the leak 'may' be under the cabinets, (after you get through the concrete and working hydronics system). Still a quick fix would be wonderful.....

Sounds like a hot water leak since your floor is warm. I was also noticing that my kitchen floor was warm (prior to realizing I had a leak). Another tip off is how long it takes you to get hot water- I didn't have to wait the usual minute or two for the hot water to run hot. I supposed I was was wasting gas by heating up water that leaked under my slab.

Until you get it fixed, I would advise you to turn off your water main when you don' t need water.

I used to be very frustrated that my kitchen faucet takes a minute to run warm. Now I know I should be thankful for that... :)

We had a small leak in the cold water pipe to the washing machine. You could barely hear it and the hole was foudn to be in the slab. Anderson Radiant heating fixed it by welding a shortcut pipe in the wall.

/Gloria

Just turned off the hotwater tank and watched the water meter keep spinning.....Guess there is more than just a hot water problem. I'd guess the cold water one might be easier to fix since it's 10x the hot water one. (At least this is my guess).

Anyone had a retro-fit done lately?

We are in Willow Glen and had a cold water leak a year ago, fairly soon after tiling our entire home with beautiful 12x12 tile. Anyway, our radiant guy found the source of the leak in 5 minutes and capped the line to stop it, without having to touch the floor. He then routed the pipes over the roof, at our request. According to him, leaks are often a function of the type of pipes used, the age of the home, and the composition of the soil. He also indicated that in our neighborhood, cold water leaks at the 40 year mark were common. His final point was that we could jackhammer up the tile and fix the leak (something that he was happy to do if that was what we wanted), but that is no guarantee that another won't happen the next day, week, or month. So we decided to get it over with and run the pipes over the roof. We are glad we did.

Cathye

Hi Mark- Just wondering what happened with your leak. Did you find the source of the problem? If so, how did you solve it?
Lynn

Confirmed at least two leaks. Decided to get a quote on a retrofit of the house.

Cathye: Who did you have do the retrofit and were you happy with them?
Thanks.

Can anyone tell me a little bit more about the retrofit? Specifically,

1. It seems like there are 4 main areas where there are water needs:
Kitchen, Laundry, Main bath, and Master Bath. Do you need to penetrate the roof in 4 spots?

2. Where do the pipes run after the enter the house? Do you need to tear down a wall. How do you deal with aesthetics?

3. How do you deal with water temperature. I assume that running water on the roof will heat up or cool down the water. What type of insulation is available and does it work well?

I will be tearing down the walls soon for some general upgrading to my home (electrical, insulation, drywall) and perhaps I could plan for the day when I need to do this. It seems like it's inevitable.
Lynn

You've kind of hit all the nails on the head. In some cases without pulling out all the walls, you may need to penetrate the walls 3X in a bathroom.
Once for the toilet, sink and shower/tub IF they are on seperate walls and you can't connect the pipes together. With your walls down, you could make this a lot simpler. Perhaps even having no roof penetration, (although with the amount of glass we have you'll probably not be able to avoid it). You can also run the pipes under the eves or underground around the house. It will also be MUCH cheaper with the walls off because they don't have to guess about somethings and put extra padding into the budget to account for problems.

For my house:
They are planning on running the cold water from the input (my garage) to the water closet with the h/w tank. (A 24' straight run for me). This would abandon the cold water line going into my slab in the garage.

Then 1" lines up out of the roof from the water closet to all places that need h20. (Branching to 3/4" and 1/2" as appropriate).

All lines across the roof insulated but in hot weather the cold water will take a while to cool. They also can put a tin/aluminum cover over the lines to help hide them.

If you happen to be planning on a new foam roof, this is a GREAT time to repipe and perhaps run more wires since all the penetrations of the roof will be sealed and hidden.

Hi Mark- This sounds like a major inconvenience- no doubt the last thing you were thinking of doing in July!

We are planning on taking down most wall for electrical upgrades, running computer/phone cable, insulation and drywall. Since I had this problem 5 years ago, seems as if I should plan on dealing with it now. I don't want to see the City of Palo Alto knock on my door again to find out why my water useage is so high again. Who is doing the work for you? Is it our radiant heat advertisers or a plumber?

Thanks,
Lynn
Palo Alto
[email protected]

Hi Mark:

I'd be glad to provide the name of the contractor that did our retrofit. Just send me an e-mail at [email protected]

C

Mark: sorry to read about your plumbing problem.
Would you e-mail the contractor that installed your Sanyo A/C system (I assume you bought the A/C system from the installation contractor).
My e-mail is [email protected]. Thanks.

A leak under the slab can be serious business. About ten years ago, I noticed my son always getting dressed in the laundry room. He was just a little kid and the warm floor was just the thing for struggling into his clothes in the morning.
It didn't take much research to find out that the heat was hot water escaping a little hole that, over the years, developed as the copper pipes expanded and contracted in contact with the aggregate stones in the cement. (They don't make 'em like that anymore. You need to put a sleeve around pressurized pipes in concrete).
Water and gas bills had gone up, but the real damage was to the soils under the house, which was sinking, actually listing. The living room floor cracked, which I only noticed when the sliding glass doors no longer closed squarely. It's pretty hilly around here. One lot nearly collapsed into the neighbor's house below because of a broken water pipe.
I called the insurance company, State Farm, who right off the bat insisted it was something they didn't cover. However, the adjuster found a little bit of mold on the carpet, and that made it a "covered" claim. Now it gets weird. They had their engineering firm come out. These guys were used to much larger projects. Their idea was to cut the walls away from the foundation and jack up half the house. I didn't think the roof would take the stress, so I got a second opinion. Sure enough, all that had to be done was to pour a new floor with killer expensive self-leveling concrete (like the stuff used in TV studios so the cameras don't bounce when rolled). It meant new doors and stucco, but was much more cost-effective and far less risky.
The estimate came to $70,000, which my insurance company offered to pay, plus putting us up in a rental, fortunately the house next door. Thank you State Farm. But I knew that a remodel this big would certainly go over budget. We had abandoned the old plumbing and re-routed everything around the outside, with no supply lines under the slab. I was happy to let it go at that, a few thousand bucks to re-pipe the house, and State Farm could keep the rest. With moving, rental, and engineering reports, their share had to be pushing $100,000.
No deal. The cracked slab did not conform to FHA standards, so the lender, who had been automatically informed, would insist on the Big Fix. (And there I thought I was the owner.) Sure enough, the remodel went way over budget, which I paid, but I don't complain. It came out nice. The house has been featured in San Diego Home & Garden and is used as a fashion photography location. (I would never own a house with pressurized pipes in concrete, no matter how well engineered. Nobody in their right mind does that big a remodel just for the heck of it. Move, it's easier.)
Don't underestimate the magnitude of the inevitable problem of leaking hot water under your slab. Usually insurance will not cover it and it must be repaired.

Rex- Wow- what a story. Makes me want to go and check my water meter now! Maybe it will make Mark feel better that his isn't that bad.

In the interest of clarifcation on this topic, I thought I would add the following. I am pretty sure it is accurate but I am counting on all of you to correct me.

In the slab there are:

1. Radiant heat pipes.
2. Domestic hot and cold.
3. Some of the electrical (most of the light fixtures are run from the panel to the light on the roof).
4. In my house I think I have one telephone line that appears in the kitchen.

Mark and Rex have leaks in their Domestic Water pipes and not their radiant heat system. When I had a Hot water domestic water leak, we opened up the slab and I noticed that the domestic copper pipes were corroded and had pin hole leaks but the surrounding copper radiant heat pipes were completely clean and shiny. I wanted to understand why so that perhaps I could have stopped the corrosion in the domestic water pipes. My question appeared in the 2000/2001 Eichler Newsletter "House of Questions". Franz Rogmans replied the following:

"There is no relationship between corrosion that may occur in radiant-heating piping located inside the slab and corrosion that may occur on potable water piping under the slab. Copper tubing is used in many applications encased in concrete without any ill effects. Statistics indicate that the corrosion that results in the failure of a copper tube from the outside of the tube wall under a slab in a potable hot water system is usually caused by thermo-galvanic corrosion when hot-water and cold-water rubes are too close together in a soil conductive enough to allow an electric circuit to develop between the tubes. In this particular corrosion cell, the hot-water tube is always the anode and the cold-water tube the cathode: thus the hot-water tubes developes the pinhole leak. There is no remedial repair other than replacing the damaged tube and separating the two tubes by a distance that can overcome the resistivity of the soil surrounding the tubes. Since on the the contributing factors in decreasing a soil's resistivity is moisture content, once an leak has occured and satured beneathe the slab, the likelihood of a second leak occuring elsewhere in the system is increased".

My neighbors have experienced cold water domestic water leaks so there may be some other chemical reaction going on. Anderson heating attributes the difference between the radiant and domestic water system to the fact that the radiant heat piping is closed loop and the domestic isn't. They can possibly explain more. The bottom line is that you can't stop the domestic corrosion but the radiant heat system should be good "for the life of your house".

Because of this, I am counting on having radiant heating but I won't be waiting around for domestic leaks since I plan to just get the retrofit during my remodel. It may cost about $13K but it's better than remodeling and and then experiencing a domestic water leak and tearing down walls. I also want to point out that several folks have lost their electrical in their slab- either partially or completely. During my remodel, I will be running all my slab electrical (what is remaining) on the roof.

In summary:

1. Radiant heat pipes- if they are copper, they will last a long time- no need to retrofit.
2. Domestic water- it will fail eventually and the retrofit will need to occur on the roof. The radiant heat companies on this site can do the work.
3. Electrical- will fail but perhaps others can comment on the longevity. Reasons may include corrosion due to moisture exposure from the slab.
4. Telephone- use as long as you can then go wireless?!

I encourage all of you to comment/verify/correct. This can all be fairly daunting but solvable.
Lynn

:wink:

As to you telephone line to the kitchen: Our house had a telephone line to at the kitchen island. When we remodeled we found that that line was actually run through its own 1/2 inch EMT to an outside wall where the telephone demarcation box is.

We were able to use the old telephone wire to pull two new CAT-5e cables through the conduit and now have both telephone and a computer network hookup on the end of the island.

We found that all the under slab electrical in our house is run through conduit (kitchen wall, kitchen island, hall washer/dryer). The conduits we needed to run wires in for the kitchen were still in good shape and could hold enough conductors for our needs. So we now have a kitchen with high speed networking and current code compliant electrical without running utilities over the roof. We did have to cut into the roof for the new lighting and to move some switches, but that is another story.

Well, I've scheduled a whole house retrofit starting on the 31st of this month. I'll continue to shut off the water unless we need it. It's now probably on 2-4 hours a day.

it is sadly informative to read this post after my neighbor/plumber has suggested that we have a hotwater leak because for the last week we've been feeling a warmness in our guestroom/master bath....and our boiler in unplugged. Ug!

Well it's mostly done. I've a repiped house. The leak has stopped. The city looked at it today and I should get a final this Wednesday. The city inspector had an interesting comment, "This is the best install I've seen" when looking at the insulated pipes running across the roof and seeing the plastic covers that will go over them.

Great work by the guys getting my house back in shape. They worked the weekend due to other pending work. Just some panels left to re-install and a couple of other minor things to finish.

Email me at [email protected] for details on the installers. I'm happy to recommend them. (They are on the Radiant Heat list).

hey
nobody commented on my last post about pipe lining, so I will mention it again. I'm finding this pipe lining option most interesting, being quite competitive with repiping prices. The pipe lining company cleans out your pipes, changing out any exterior piping (sink, bathroom, etc.), and then shoots a toxic-free epoxy into your pipes, essentially sealing/lining them from corrosion and leaks, lead, etc. This process carries a 10-year warranty (particularly with the company I am researching) and has been used commercially for many years and in the last 15 years or so with residential homes. Has anyone had this done? It seems like a great alternative to repiping if it truly is as good as they make it out to be...

I never heard of the process . . . and I would question claims of a "better mousetrap". Here are some examples - - indoor kerosene heaters (20 years ago), silicon, aluminum wiring and fire retardant wood. Here's the latest I've come across - - non-stick cookware when used above certain temperates (Dupont admits to it) and leaching plastic formula bottles (the same bottles I've used to feed our only child; the first life born in our family in 17-29 years and I'm giving her carcinogens).

So Cindy, non-toxic epoxy sounds too good to be true. Hot 120 degree water running through 100 ft of epoxy lined tubing can pick up foreign things. Are you sure it's not from the manufacturer of the battery operated fat reduction waistband?? :wink:

P.S. - - I sympathize with you on the hot water leak, especially since you only moved in a short while ago (I think). It's a repair-vs-replace question - - are you spending 50% to get 25% lifespan? Also, no experimental surgery for me unless there's no other choice.

Brookeworld--you are definitely right that it is best to avoid experimental surgery at all costs! but I can't help thinking that this new pipelining approach may be a realistic alternative to completely repiping, especially after the reps came today to explain their process. see for yourself:

http://www.aceduraflo.com/

I will probably fix my slab leak conventionally by jackhammering (since it is covered by my home warranty). But I am going to give this some serious thought as a future preventative measure (and in the meantime do some more research and call all of their references...)

Cindy

Eichlers are new to me; I'm from the East Coast where many homes have domestic utilities in the basement or run pipes through walls and ceilings (1 story houses in the East are as common as 2 story houses in the West; and no flat roofs) - - so when there are leaks in ceilings or walls, they open them up and do repairs. Out here, putting so many things in the slab (around moist soil) seems like silicon implants - - what were they thinking of at the time.
You've read about several people who decided to re-pipe to avoid jackhammering or incurring the cost to repair a 2nd leak in the slab, but the discussions gloss over how expensive and disapppointing it is to have these "end-of-life cycle" Eichler problems. So, do you do the big fix (and correct original design or building defects) and re-start the clock or do something short of that? Quite frankly, it depends on financial resources and how long you're going to be in the house.
I really don't think you can assess the re-lining option properly - - it takes 10+ years to know whether a bulding technique (or medical device) proves correct so it is caveat emptor.
I think you will be disappointed with what the warranty company will pay - - in my my July 4 Water Heater experience, the company paid $270 for a 40g tank and I paid $288 for the deductible, EQ bracing & Sunnyvale permit. It would not surprise me if your warranty company will just pay for repairing the pipe and not the cost to get to it (like the slab work) and insist on a specific contractor (just like a HMO) - - I don't know, but be prepared to be disappointed. (In my case, I should have gone to a 50-60g tank after-the-fact reading in Consumer Reports that it cost the same to operate, but I was too distracted and wanted the problem fixed ASAP).

Good luck.

thanks brookworld for all your invaluable info. luckily my warranty does pay for all of the slab work, filling with concrete, etc., and they will pay me out the money if I want to hire someone else instead. But they have been hard-as*es with other stuff so I get your point. Earlier this year the automatic shut-off vent on my boiler broke--a real pain because the boiler wouldn't function without it. And of course the warranty would only fix the boiler and not any part of a vent. They didn't care that the malfunctioning part made the boiler useless.

Anyhow--I too am familiar with traditional home maintenance and this Eichler stuff is all new to me! But I do love my home so I will make an effort to not get to frustrated each week when something else goes wrong!! :wink:

I am on my sixth floor leak (been in the house 25 years). My home is in Castro Valley. The plumbers detected the leak, but when they jackhammered the section where the leak was supposed to be, they found that the floor was abnormally thick (by the sliding door to the atrium) and said they might not be able to fix the leak if it is where the extreme thickness is. (This was after digging up some of my tile in the process).

Now the leak has sealed itself. This happened to me with a previous leak, but it came back after a couple of years.

I have had neighbors who have had their pipes rerouted into closets and then up over the roof and in the kitchen area, behind the cabinets under the sink and up to the roof (with no holes put in the walls except to the roof). Has anyone else had their pipes rerouted in this manner, and if so, what was the cost? :(

The plastic lining solution sounds iffy to me too. Why take a chance, considering the risks? It's much nicer to check something like this off the list rather than to have to keep checking up on it.
One more plus for the re-pipe option: We're just putting in a patio and re-planting the back slope. It is much easier with the pipes outside the house. We just "T-off" here and there and we got water wherever.
As to the EOL (end o' life) argument, never say die with Modern design. Rather than worry about this being a new heart in an old man, think of it as continual renewal, life everlasting, that sort of thing. It's a house, not an old man. And in keeping with Modernist doctrine, it should be improved with use: Form just keeping up with Function.

Hi,

I've recently become an owner of a 40+ year old Eichler. What indications are there for a leak?

The sink faucet takes about 2-1/2 minutes to warm up. The master shower takes about 2 minutes. The secondary bathroom sink and tub takes about 1 minute to heat up. Even my kitchen sink has about 30-45 second delay when it is located less than 8 feet away from my hot water heater. Are these signs for a leak?

Thanks,
Wendy

Those are not signs of a leak.

The easiest way to find a leak is to shut off all the water and look at the water meter.

What you describe is not really an indication of a leak. A leak in the hot water system would cause the water to become hot sooner rather than later since the hot water is constantly running under the slab.

:( Rex,

What was involved in rerouting the pipes around the outside of your house and what was the cost? Was the roof involved or were they rerouted around the base of the house?

You read my saga, so you won't be surprised if I say whatever it takes to get water out from under the house, it's worth it. Especially if it's under pressure (supply and not waste) and especially especially if I'm paying to heat it.
I agree, long warm times are actually counter-indications for leaks. My plumber says if it takes more than 30 seconds for the hot water to get to a fixture, an in-line heating unit may be cost-effective. (I have a new respect for the trade and value the professionalism of "my plumber" more than "my doctor" in these post-health management times, but I stray.)
This is not a low-bid, butt-crack plumber job. On the other hand, worry if the guy shows up in a Caddy like the father in Moonstruck (wasn't that the movie?). This job will take some creativity because they have to figure out a "best path" with many un-associated variables (pressure drops, access, interference with other services like wiring). Major points off for going over the roof. Bonus point for minimal dry-wall busting, saving you hiring drywall guys and painters, which is the beginning of a major remodel, "while we're at it," if you know what I mean.
When they trench around the outside, it's a good time to reconsider the shrubs against the house. Face it, they have no practical value and plenty of risk, hardly the Modernist Way. Make sure trenches are very well-compacted when re-filled. It will take a few years maybe, or the next heavy rain, to show even ditch-diggers should value craftsmanship.
As to cost, my insurance company and I paid about $8K in 1995 down here in San Diego for 2K sq ft house with excellent access, due to an excellent floor plan. (HORD, Heftmann's Only Rule of Design: A good design is even better than you think.) They ran supply lines in trenches around the outside of the house, a few feet away from the foundation and in insulation, which may be overkill, but if I did it again, I'd add a plastic shield above the pipes to warn anybody excavating. All that to say, don't do this cheap. Cheap paint you do over. Cheap plumbing under or even near a slab on grade can cost big, fast. Ask the guy up our hill whose embankment slid down into a neighbor, damaging two houses and making the newspaper while he was trying to sell the place.
Honor thy plumber.

Rex,

Thank you for your reply. I take it you don't recommend going over the roof. I had thought about doing that when I had my foam roof recoated. some of my neighbors had the pipes put in closets and behind appliances so that they didn't have to go through walls (quite awhile ago). I don't know about code rules at this time, however. Did you research costs, etc., re going over the roof compared to going around the house?

I appreciate your input.

Nancy

You asked. Please factor in that I am a design purist.
1. Over the roof is ugly. Roofscape matters, especially when you live on a hillside. People think the roofs of Paris are charming but they just happened without intention, and if their roof is a mess of vents and a/c units with relics of the days of rooftop antennas, it just has to be so ignore it. No. Ugly is where you see it. It indicates bad design.
2. Poking holes in the roof is asking for trouble. I love water dearly, but it is diabolical about getting out of where you want it and into where you don't. Not just sometimes, but always. To paraphrase, "what can leak, will." Not just a cute paraphrase, it's physics.
So, no, I didn't cost out an overhead route. I did spend some time with "my plumber" working through alternatives, which lead to re-locating the water heater (outdoors in a shed) and adding hose bibs where the pipes go into the house. The spigots are coming in handy locating the water lines now that we're re-landscaping.
We snuck under bathroom vanities (easier to patch) and added a spigot for hosing out the all-tile bathroom. It all takes some figuring out.

As they say in sales, it's not a problem, it's an opportunity.

Rex,

Thank you again for your input.

Nancy

As stated earlier, this isn't a leak. Anyway, I fixed this problem by putting this into the vanity of my guest bathroom. Works flawlessly and easy to install once you run the electrical.

Bump...this is an old discussion but thought I'd bump it to the top again...

I don't have a slab leak (we fixed and did not re-route the pipes) but I have had one in the past and found something interesting I wanted to pass along. The hot water pipe that was pulled out of our slab looked like these photos in the web link below. Our pipe was actually resting in the soil just below the slab. There are many reasons for leaks but I believe we had some soil-side corrosion (as opposed to water side corrosion which is also discussed).

The company that addresses these leaks (Bencor) is located in San Diego and they are not interested in residential- they basically take on large home developments and apartments.

I thought I would post this anyway to generate discussion on the cause. I thought this might be a potential solution. If you have any comments on your type of leak, I'd be interested in hearing them. Also if you know anyone that would be willing to install cathodic protection like this on a home in the Bay area, let me know.

I'm planning a remodel and floor and need to take into account another potential leak. A solution other than repiping would sure be nice (and a crystal ball).

Here is the link:

http://www.ebencor.com/cathodic.html#works

This company has a parent company (coppercare) and the equipment can be bought separately. Here is what Bencor installs:

http://www.coppercare.com/cathodicprotect.html

Lynn