water leak under slab

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can someone help us we have got aleak under our house it is a slab foor and i do not have a clue how to find or fixwe can only trun on the water to flush or wash and then we have to turn it off we have a4 year old so we cant plan when to do this so it means we have to turn it on and off all the time we cant pay someone to fix until we get taxes back and maby not then if is alot help if you can lots of thanks zero poof @ fred

-- jeff (zeroman767@aol.com), February 14, 2000


you dont say if your on city water or your own well.If city water contact the water dept.

-- stan (sopal@net-port.com), February 14, 2000.

OK, Jeff, first of all, how old is the house/plumbing? How do you know you have a leak? Is water showing at one point? Like the last person said, are you on a meter (city water system), or on your own well? You are probably going to have to plan on jackhammering along the line of the plumbing when you know where the pipes run, replace the broken pipes, which are probably corroded from being in concrete, unless they are newer and PVC. Not an easy job, in any case. If you are handy and can rent the equipment, it will just be time consuming and messy. Lots of dust, noise, etc. Store water in jugs/empty milk, detergent, etc if you can to use to flush and wash with so you don't have to turn the water on as much, and also have as much on hand (probably have to fill somewhere else if you don't want to leave the water on long)for when you are working on the pipes. Maybe with some of these questions answered, some plumber types can give you more specifics. Good Luck! Les & Jan

-- Les &Jan Bullock (Janice12@aol.com), February 14, 2000.

Jeff; i am a plumber. Depending on the age of your home, you may have either galvanized, or copper piping. The first thing is to determine where the leak is. You can rent sensitive sound equipment that you use with earphones to locate the leak. Sometimes you can use a common stethoscope. Also feel for warm spots on the floor, because more often than not, the leak is a hot water pipe.

Once you have located the leak and turned the water off, you must break through the slab. Again, you can rent a small jackhammer, but sometimes you can just smack it real hard with a sledge and break through. Either way you must open up a hole over the leak and expose it. If it is copper, you can cut a small section out, slip a copper coupling in, and silver solder it. This takes some degree of skill. Do not just solder it like you would copper piping above the slab. It should be silver soldered if it is under the slab.

If the pipe is galvanized, it probably is very old. You need to make a decision as to whether to repair old galvanized, or just repipe. If it is very old, it is probably weak in many spots and you may get more leaks. Anyway, to repair it, just saw out the bad part and use something called a compression coupling which has nuts on each end. Good Luck

-- Jimmy James (fishuntr@lucernevalley.net), February 14, 2000.

Hi, Jeff:

When a pipe sprung a leak under the slab at my mom's house, the plumbers were able to bypass the trouble spot by running new pipes from the main to the inside (they went up an outside wall, through the overhead crawlspace and down to the connections indoors). I don't know whether that kind of fix is possible at your place, but I know it made a big difference in what the repairs cost her.

If you have containers you can store some water in, you won't have to turn things back on to flush...just pour water into the bowl and you're done. Or you could try what Mom and I did for a few days: just fill the tub and draw it out by the bucketful as needed, if you can keep the four-year-old out of the "pool."

Hope this helps. I recently went through a bad patch of plumbing problems myself, and it's no fun at all! -- Christine

-- Christine Trowbridge (cytrowbridge@zianet.com), February 15, 2000.

whoooooooo hooooooooo i have a better answer for you than jack hammering and digging up the concrete foundation......i had the same problem last summer, and let me tell you about this.

keep your fingers crossed that this will also work for you

the copper pipe in my foundation is 5/8 or 3/4, i forget which. anyway, my plumber-friend was able to get the next size smaller copper tubing and snake it through the older larger size. he had to investigate some at first to determine which line it was, as i have 2 bathrooms that back up to each other. anyway, he was able to start at the hot water tank, cut the bad line there, and snake through the smaller copper tubing through the existing bad line. the only trick was, as my plumber - friend explained to me, was to keep my fingers crossed and hope there were not any sharp bends that might "hang-up" the new line. anway, it worked !!!!!!!! went right through just beautifully and easily. he had told me to expect possibly a reduced water pressure, but i cannot tell a bit of difference, that part of the house has the same or more than enough water pressure and volume, i can't tell the difference when i shower or run water.

let me tell you i was SO pleased that this worked, saved me a small fortune $$$. my plumber-friend told me if it had not worked, he would have had to run tubing up into the attic, through the attic and down to the wall between the bathrooms, and that would entail some carpentry, drywall and painting/wallpapering work, fortunately we did not have to do this. i live in oklahoma, our winters are not super cold so this 2nd option would haved worked ok here, but it might not have worked well up north where it gets super cold and the attic pipe might have frozen or burst, but i guess if you had to do this, you could insulated and heat tape the tubing.

bottom line, the point is, it is NOT always necessary to jackhammer up a concrete foundation. not only is that very expensive, but then you have to do new carpet, linoleum, slate or quarry tiles, whatever.

good luck !!!


-- gene ward (gward34847@aol.com), February 15, 2000.

An old fellow once told me this, and I will admit right now, I know next to nothing about plumbing! He mentioned, when you where installing a new water pipe under a slab, or other inaccessible area, or where you might later build over the water line, to go right ahead and run it through a larger support pipe at that time.

-- cinnamon (homesteader145@yahoo.com), February 15, 2000.

Jeff, I'm a general contractor, and I do all my own plumbing. There are a lot of creative ideas to choose from here. If it were my house, I'd investigate the idea of snaking a smaller diameter pipe through the old pipe, although I think the likelihood of being able to do this is slim, due to pipe joints. Even if the pipe run is straight, you'd still likely have to break through the slab wherever the pipe goes into the slab and comes back out of it.

Assuming that snaking a new pipe were impossible, I'd think about rerouting the pipe either through the attic, and down through the walls, or around the perimeter of the house, then into the wall behind the fixtures. It would all depend on the layout of the house, whether it's easier to cut into the outside siding or the drywall, plaster, or wood (or ??) on the inside. Also would depend on the climate. If you run the pipe through either a wall OR the attic, make sure that you run the pipe on the heated side of the insulation! Lots of folks don't (even some professional plumbers, who should know better), and the result is almost always frozen pipes, often with terrible damage to walls, ceilings, floors, etc.

Jackhammering up the floor is a last resort, IMHO. BIG job. Big expense. And very, very messy. I also agree that it's likely that if the pipe is bad in one place, it's likely to be bad elsewhere. It would be good to know the age of the house, or even better to know what the pipe is made of. If it's galvanized, it's probably rusted out due to its age. If it's copper, it may be that your water has low pH, and you should have it corrected, as it will continue disolving your copper pipes and causing potential health problems (copper poisoning)

Gene, did your plumber use flexible copper? Didn't your pipe come into/out of the floor vertically? If so, how did he deal with the elbow where the pipe turned from vertical to horizantal?

Jeff, if you do have to replace the pipe under the slab, be sure to use type L (heavy wall) copper, not type M. Shame to go to all that work and have to redo it any sooner than necessary.

Good luck!

-- jumpoff joe (jumpoff@echoweb.net), February 15, 2000.

My family and I would like to thank everyone for your responses to our problem that we have. I am sure with all of your great suggestions that we will find the best way to fix our leak.

Thanks again for all your help.


-- Jeff (zeroman767@aol.com), February 16, 2000.

To find the leak,put a screwdriver to your ear.(handle to head & point to faucets all through the house & where ever you hear it running the loudest, thats where your leak is. Go outside & dig below the foundation & then to your leak.What ever you do,don't mix your metals or you will set up a electrolysis & then you will have another leak later on. To see if the leak is on the hot water line,cut off the cold water valve on top of your water heater.If that stops the leak then you know if its the hot water line.If so, leave the valve cut off & use all the cold water lines until you get it fixed.

-- Joseph Vincent McAlister (joetheplumber@webtv.net), May 09, 2002.

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