Plumbing Question - Water Leak Under Concrete Pad Foundation

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Plumbing Question - Water Leak Under Concrete Pad Foundation

Zach Schwarzmiller
Investor · Snohomish, WA · Member since 2013 · 629 posts · 84 votes

Greetings. I was sad to get a call from the City today letting me know my water consumption has doubled for this billing period. I just replaced 6 new water lines and meters in my building down the street and was hoping to not have to do anything else with damn water lines (my grandpa's and father's main water lines broke the same week mine did - odd????!). Anyways, it is what it is. It's a duplex on a concrete pad foundation. I've turned off the water shut off valves in each unit to verify it is indeed from the meters to the shut off's and it's still spinning (takes about 6 seconds to make one full rotation on the meter. When the sink is full-blast it takes about 2 seconds to make one full rotation on the meter). I have dug the 5 feet distance from the meter to the concrete foundation and have not located any water leaking. I am assuming I need to hire a water leak detection company to use some sort of moisture detection equipment. The worst part is i just refinished my concrete floors, and now I might have to cut them up to get under them - $H*T!. Anyone have any thoughts on the best way to approach this? What do other people do when this happens? Is it best to just fix the leak or is there a good way to replace the water lines? This property is in Snohomish County, Washington State. Thank You!

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Vic Stezin
Easton, PA · Member since 2015 · 12 posts · 3 votes
11y

In the end it will be less intrusive to abandon the defective line and install a new one in a location that it can be accessed in the future. Digging up concrete is a mess that is best avoided. A good plumber should be able to help you figure out a new route.

Vic

Easton, PA

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  • George P.
    Property Manager · Livonia, MI · Member since 2011 · 4k+ posts · 1k+ votes
    11y

    ouch! that will leave a mark on your wallet. isn't any water coming up through the floor? or it's seeping immediately down and no indication on top?

    you will have to either re-pipe up through the walls or bust concrete. no other way around it.

    0Reply
  • Vic Stezin
    Easton, PA · Member since 2015 · 12 posts · 3 votes
    11y

    In the end it will be less intrusive to abandon the defective line and install a new one in a location that it can be accessed in the future. Digging up concrete is a mess that is best avoided. A good plumber should be able to help you figure out a new route.

    Vic

    Easton, PA

    2Reply
  • Zach Schwarzmiller
    OP
    Investor · Snohomish, WA · Member since 2013 · 629 posts · 84 votes
    11y
    Originally posted by @George P.:

    ouch! that will leave a mark on your wallet. isn't any water coming up through the floor? or it's seeping immediately down and no indication on top?

    you will have to either re-pipe up through the walls or bust concrete. no other way around it.

     There is no water coming up through floors anywhere, no indication on top at all, unfortunately! I would love to come up through the wall. Does it make sense to run line from meter and drill it upward into the wall? and just run along walls?

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  • Jassem A.
    Investor · PA · Member since 2013 · 1k+ posts · 602 votes
    11y

    I would re-pipe up through the walls rather than have to bust up the concrete.  A good plumber could tackle it in a day or two.

    He'll probably drill into the exterior sheathing and run it into the wall that way and then put a foam jacket around the exposed pipe rather than drill through the slab and sill plate.

    1Reply
  • Zach Schwarzmiller
    OP
    Investor · Snohomish, WA · Member since 2013 · 629 posts · 84 votes
    11y

    Okay, I have a thought... I am thinking I am going to abandon the old water line and install new ones. I have a whole bunch of poly left over from my other six meter installs. Outside of both units there is a drain for the relief valve which runs through the interior walls from right nearby where the incoming water shutoff valve is. I am thinking I am going to run poly through the yards to the area where that relief valve is and then saw cut the exterior concrete up to the exterior sheathing and then pop the new line into the unit and run it adjacent to the relief valve back to the main water faucet and connect into that. This would make it so I don't have to mess with any concrete and I would be working with a fresh line. I might even install a new meter while I am at it so the units are individually metered, TBD on that part. 

    New question, if I am running the poly to the house, and the house is all plumbed with copper, should I switch to copper at the house or can I continue to run my poly up to the water shutoff through the walls? It would seem that should be okay as it's kind of a nice flexible pipe compared to copper.

    Thank You!

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  • Jassem A.
    Investor · PA · Member since 2013 · 1k+ posts · 602 votes
    11y

    You can mix whatever type of pipes together that you want.  Believe I have one property with a mixture of cpvc, pex, copper and iron pipes.  The most recent house I had plumbing work done, used all push fittings and pex.

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  • Zach Schwarzmiller
    OP
    Investor · Snohomish, WA · Member since 2013 · 629 posts · 84 votes
    11y

    Problem Solved:

    0Reply
  • Jim Shepard
    Investor · Edwardsville, IL · Member since 2015 · 432 posts · 481 votes
    11y
    I know your problem is now solved but for the future here's how one of my duplexes was fixed. It too is on a slab and had a water line go bad. The plumber used directional drilling like the utility companies use. The only concrete that was broke up was a one foot square area. Not sure of the cost as it was already done when I bought it.
    1Reply
  • Zach Schwarzmiller
    OP
    Investor · Snohomish, WA · Member since 2013 · 629 posts · 84 votes
    11y

    @Jim Shepard

     - Thank You. I think that would be a great route to go, but I am too cheap so I ended up just doing it myself. On the plus side, I got a good workout and was able to control the surroundings of my back-fill so this won't happen again. I ran into three separate leaks before I got to the concrete foundation just from old chunks and rock and concrete being in the dirt. Now I have top soil which is 1/3rd sand essentially 6"-1' all around the new poly line - some peace of mind for me, personally. On the other side, when I get to it (vacant doing updates so not such a hurry), I will rent a ditch witch, I am way too sore from digging the 30' trench. 

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  • Gilbert Dominguez
    Investor · Chicago, IL · Member since 2015 · 677 posts · 309 votes
    11y

    Completely empty the water lines. At the main install an air gauge. One that comes with a meter. Fill the line with air and observe the gauge. If you are losing air pressure then you have a leak somewhere. If your gauge remains steady then the problem in on the supply side. This will at least establish if the leak is on you or on the city, Before you spend big money. 

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  • Edward Mccracken
    Real Estate Investor · Sauk Village, IL · Member since 2015 · 78 posts · 30 votes
    11y

    Man I had the same problem in a finished basement and how do you find the leak right?  My leak was before the meter in the concrete.  I didn't know that until I kept on vacuuming water from the carpet and it wasn't stopping until I called the waster company to shut the main off.  The roto rooter guy came out and said something crazy like it would cost 80 per sq ft of them digging to find the leak and he had an idea where it was, he was way off.  I called the leak detector guy that uses sonar equipment that charged 500 per hour. lol... He found it with in the hour and guessed was the exact problem was.  The problem was copper coupling was underground and it came loose.  That could have been the best 500 I ever spent.  

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  • Raymond B.
    FL · Member since 2009 · 2k+ posts · 357 votes
    11y

    @Zach Schwarzmiller,

    To make the @ work, do the following:
    Hold down the shift key and type @?
    Look below this Window, and you will see a list of names of people that have posted in this thread.
    Click on the name of the person that you want notified via an email, that you responded to them.
    If you are a Colleague with anyone that has NOT posted in the thread, and you want them to see your post, hold down the shift key, type the @ and the first 4 letters of their First or Last Name.
    Then look below this Window and click on that person's name.
    Raymond

    1Reply
  • Account Closed
    Investor · Central Valley, CA · Member since 2012 · 6k+ posts · 3k+ votes
    11y
    Originally posted by @Vic Stezin:

    In the end it will be less intrusive to abandon the defective line and install a new one in a location that it can be accessed in the future. Digging up concrete is a mess that is best avoided. A good plumber should be able to help you figure out a new route.

    Vic

    Easton, PA

    I've been wondering about this when it comes to slabs.  I live in a place with no hard freezes so, technically, with the right layout, you could abandon the old line and tie-in with a new line, digging trenches on the perimeter.  I rehabbed a 3/2 house, 1990s construction.  Both baths, kitchen and laundry area in garage were situated so there were no under slab supply lines.  However there are so many 1950-70s slab houses where no thought was given to pulling the line into the middle of house under concrete.....with no access for repair or replacement.  Is the only solution in those cases to dig up the slab? 

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  • Zach Schwarzmiller
    OP
    Investor · Snohomish, WA · Member since 2013 · 629 posts · 84 votes
    11y
    Originally posted by @Account Closed:
    Originally posted by @Vic Stezin:

    In the end it will be less intrusive to abandon the defective line and install a new one in a location that it can be accessed in the future. Digging up concrete is a mess that is best avoided. A good plumber should be able to help you figure out a new route.

    Vic

    Easton, PA

    I've been wondering about this when it comes to slabs.  I live in a place with no hard freezes so, technically, with the right layout, you could abandon the old line and tie-in with a new line, digging trenches on the perimeter.  I rehabbed a 3/2 house, 1990s construction.  Both baths, kitchen and laundry area in garage were situated so there were no under slab supply lines.  However there are so many 1950-70s slab houses where no thought was given to pulling the line into the middle of house under concrete.....with no access for repair or replacement.  Is the only solution in those cases to dig up the slab? 

    That is what I did - I ran the trench around and cut into the house where it was best to hook into existing plumbing.

    0Reply
  • Account Closed
    Investor · Central Valley, CA · Member since 2012 · 6k+ posts · 3k+ votes
    11y
    Originally posted by @Edward Mccracken:

    Man I had the same problem in a finished basement and how do you find the leak right?  My leak was before the meter in the concrete.  I didn't know that until I kept on vacuuming water from the carpet and it wasn't stopping until I called the waster company to shut the main off.  The roto rooter guy came out and said something crazy like it would cost 80 per sq ft of them digging to find the leak and he had an idea where it was, he was way off.  I called the leak detector guy that uses sonar equipment that charged 500 per hour. lol... He found it with in the hour and guessed was the exact problem was.  The problem was copper coupling was underground and it came loose.  That could have been the best 500 I ever spent.  

    I've used those guys twice so far (American Leak Detectors).  Both times he left a big X on the spot and the plumbers knew where to start with the jackhammer.  What did people do before the sonar technology?  Do water witches also find leaks?

    0Reply
  • Matthew Paul
    Severna Park, MD · Member since 2013 · 7k+ posts · 7k+ votes
    11y
    Originally posted by @Zach Schwarzmiller:

    Problem Solved:

    Does it freeze where you are ?   That looks like PVC pipe , it will work , but its UV sensitive it will get brittle over time.

    1Reply
  • Hugh Ayles
    Cedar Park, TX · Member since 2015 · 377 posts · 200 votes
    11y

    To add onto Matthew Paul's comment, you have mixed material, they are exposed and not insulated.

    Different materials expand and contract at different rates.  You've mixed 3 materials in a very short, exposed run.

    0Reply
  • Jerry Powers
    Real Estate Investor · Tulsa, OK · Member since 2009 · 26 posts · 8 votes
    11y

    My thoughts exactly, Hugh. Mixing different materials that expand and contract at different rates, on the exterior in a very cold climate, is a recipe for disaster. Short of replacing the piping with consistent material, heat tape wrapped around the piping and enclosing it in a highly insulated enclosure is going to be necessary. 

    0Reply
  • Zach Schwarzmiller
    OP
    Investor · Snohomish, WA · Member since 2013 · 629 posts · 84 votes
    11y

    @ Matthew

    @Matthew Paulundefined

     @Hugh Ayles@Jerry Powers

    It's worth mentioning, I sleeved the pipe going into the ground in 3 layers of insulation and built a box around the outside of the building which is stuffed with insulation. I did not show a photo of that as you really could not see the fix, it just looks like a box on the side of the unit.

    0Reply
  • Matthew Paul
    Severna Park, MD · Member since 2013 · 7k+ posts · 7k+ votes
    11y

    If you are in a freezing climate , all the insulation wont do a thing . That pipe needs to be brought into the house below frost line into a heated area . It will freeze 

    This past winter here in Maryland , my mainline froze in the ground , next to a retaining wall , pipe was 3 ft down  but was 1 foot from the wall .  Dirt is a good insulator , but the cold eventually gets thru . 

    1Reply
  • Kurt Winsley
    Investor · New Concord, OH · Member since 2015 · 25 posts · 3 votes
    11y

    One other issue you may run into is that most places don't like to see schedule 40 PVC used as a potable water supply. The only PVC product that most codes approve for potable waterline is CPVC (the off-white stuff). We don't use it because if it does freeze, it will crack and as it gets older, it gets more and more brittle. If you get inspected, you may have a fine to pay. In our area, we usually run the black waterline into the house (underground, as we are susceptible to freezing here) and transition to a shutoff once we are in the house. We are required to sleeve it with a piece of PVC or an actual sleeve where it penetrates the foundation.

    Picky details like codes aside, you did a good job keeping it neat! Hope it works out well for you. Leaks are no fun to deal with, that's for sure.

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  • Zach Schwarzmiller
    OP
    Investor · Snohomish, WA · Member since 2013 · 629 posts · 84 votes
    11y

    @Kurt Winsley thank you! I actually did the other side in PEX and I am happier with that. I used the crimpers instead of shark bite and I think overall it feels more sturdy. I want to build a cabin myself and after trying all these different types of plumbing on the rentals I think I may go with continuous sleeved poly into PEX. I have CPVC on two triplexes build in 1998 all units are townhouse so three bathrooms and every so often it does indeed give me some trouble. I took those issues into consideration on that PVC and made sure there was nothing under pressure that could be upset over time! One year ago I could barley hook up a kitchen sink. 8 water lines later I think I'm starting to understand a little about plumbing - hahah!

    0Reply
  • Kurt Winsley
    Investor · New Concord, OH · Member since 2015 · 25 posts · 3 votes
    11y
    Originally posted by @Zach Schwarzmiller:

    @Kurt Winsley thank you! I actually did the other side in PEX and I am happier with that. I used the crimpers instead of shark bite and I think overall it feels more sturdy. I want to build a cabin myself and after trying all these different types of plumbing on the rentals I think I may go with continuous sleeved poly into PEX. I have CPVC on two triplexes build in 1998 all units are townhouse so three bathrooms and every so often it does indeed give me some trouble. I took those issues into consideration on that PVC and made sure there was nothing under pressure that could be upset over time! One year ago I could barley hook up a kitchen sink. 8 water lines later I think I'm starting to understand a little about plumbing - hahah!

    Excellent! Pex is our waterline of choice and has been for a while. It is a little harder to get it looking neat, but so much easier to work with in general. Congratulations on your success in improving your skills! Keep learning!

    0Reply
  • Nicholas Q.
    Investor · Seattle, WA · Member since 2016 · 40 posts · 12 votes
    6y

    @Zach Schwarzmiller, I just stumbled across this post because I am having similar issues with a plumbing leak under the slab.  In my case, I didn't end up having to tear up the slab because the leak ended up being just outside the foundation, so it was an easy fix.  

    The problem is that the water leak seeped into the downstairs unit of a duplex and destroyed the flooring.  I incorrectly assumed that the flooring replacement would be covered by insurance.  They are telling me that even though the initial causing event was a burst water pipe, there is a clause in the policy that does not cover ground water seepage.  I've argued for days that this is not "ground water" and that it is due to a broken pipe.  It looks like I'm going to lose this battle.  It's not a big deal because I think the cost to fix the flooring is minimal, but it is more on principal.

    It sounds like you did not have any damage to the dwelling as a result of your water pipe issues, so you didn't file an insurance claim, is that right?

    I'm curious if any other BP members out there have thoughts on how to get this loss covered by insurance.  I just read a separate post suggesting that investors should only have the absolute minimum insurance coverage for catastrophic events only.  I'm starting to understand why.

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  • Zach Schwarzmiller
    OP
    Investor · Snohomish, WA · Member since 2013 · 629 posts · 84 votes
    6y

    @Nicholas Q. Correct - there was no damage to my building at all. I just fixed it myself and moved on. Sorry to hear that happen though, sometimes those battles are easier just to do it yourself I feel like. I had forgotten about this, 4 years later my fix is still working great - lol.

    1Reply
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