House Water Leak – Long

[lbperry]

My Brother-In-Law died several months ago and since his only heir, a daughter, lives in another city; it has fallen to my wife and myself to assist in the clearing out and preparation of his house for sale.
The house is a fairly standard single story brick with 3 BR, 2 BA, LR, DR, Kit, Garage; it also has a pool. It is on a slab with what I believe is copper piping. I believe it is approximately 25 – 30 years old.
Recently, his daughter who is receiving all the bills concerning his home, said the water bill has been going up the last few months. During this period the house has been unoccupied. We check it regularly to make sure it’s OK. It has always had heat in it (the weather around her hasn’t been below freezing around here anyway).
Once we found about the unusual water usage we started trying to check things out. The water department says there is definitely water usage continuing. We started checking out everything we knew to check…toilets leaking, any evidence of water leakage in house, water heater operating OK, any wet areas around yard or pool plumbing (pool had been winterized and covered several months ago), outside faucets leaking, etc. We finally turned the water off at the meter (there’s no inside shut-off valve) except when we turn it back on to search for leaks.
We have someone coming out to check out an old unused sprinkler system to make sure it has been shut off at the source (water meter). We checked it and it is shut off at the control panel. A helpful HVAC service man who came in to do semi-annual maintenance on the system was kind enough to spend an hour helping look for leaks in the house/yard even though it would have no connection to his HVAC system.
If nothing is found to be leaking with the sprinkler system, I’m about at the end of the things I can think of to check, unless you guys can give me some more ideas. If I call a plumber in at this point; do they typically have the leak detection equipment to find the leak?
I was talking to a friend of mine last night and he said he has about the same age slab foundation house with copper piping and a couple of years he had a leak that they somehow determined was in/under the slab and they had to replumb it by going thru the attic. With the plumbing cost and the wall and ceiling sheetrock damage repair, it turned out to be pretty expensive.
Any ideas on how to find the lead and what I might be looking at? I’d appreciate any ideas, suggestions or comments at this point.
Thanks,

 

[The Cobbler]

I would be sure the irrigation system is totally off, then try an air pressure test to see if it is indeed leaking. then try to isolate the area that is leaking . eg, narrow it down to hot water, cold water, pool fill, etc etc.

 

[rburke65]

Does all the house plumbing run undertheslab?

 

[The Cobbler]

another common area to look at would be the toilet(s) the flapper can be slowly leaking down and the ballcock opens to refill every so often. if no one is there for longer periods of time, it may go unnoticed ..

 

[Richard Cranium]

to check the toilet tank, put some food coloring in the tank, then what and see if it turns the water in the bowl that color?

 

[kellymc]

Is the neighbors lawn really green?

Could someone be running a hose to water their plants /lawn since they know that nobody is living there?

 

[DAVE VAN]

Turn off the supply valve where the city water line comes into the house. If the meter keeps running the supply line from the meter to the house has a leak. I have seen that a lot in that vintage of a house and no puddle or soft spot will show up in the yard.

 

[Daedalus]

You don't suspect the pool??? And just cause the sprinkler controller is shut off doesn't mean the valve isn't broken. If no one is living there and there's recordable usage (i.e., at least 748 gallons a month) then there is a large leak somewhere. It sounds like there's only 2 or 3 places where such a leak wouldn't be obvious.

 

[jgbnm]

At that age, it could have been built using polybutylene piping from the street and or inside the house, including in the slab. Known to leak, particularly at the junctions. Lots of info online. Sometimes easy to identify, sometimes a bit harder. Sometimes there can be a mix of copper and polybutylene in a house as well.

Sent from my Nexus 7 using Tapatalk

 

[jboehm]

What exactly do you mean by the bill is going up? Just monetary part or has the consumption increased and if so by how much? Water departments can be shady so don't trust what the say.

 

[jask]

If the meter is accessible you can check the gauge to see the rate of consumption... try shutting off the main supply inside the house for 24H and see if consumption decreases. I do not know about your part of the world but around here pools do not have auto top off, so like the above poster I would suspect a leak between the street and house or in an irrigation valve that is inline before the house.

 

[CTyankee]

I'm confused..Is the water meter inside the home or outside? If the meter is inside the home and the leak is between the street and the home...you shouldn't see any increase in water usage.

 

[jask]

no you will not, but if you have a curbside meter and shut the house down you will know where not to look, if you have a meter in the house the sprinkler ( irrigation line ) will be on the house side of the meter, and should allow you to shut off the irrigation the house individually.

 

[RVDan]

My house and a lot if my neighbors had copper leaking under the slab when the houses got to be 25 years old. I'm currently against code running through the attic and down an outside wall but damn, blowing up the slab is way too invasive.

 

[theundermount]

My suggestion would be to sound the pipe coming into the house with a listening device. If the leak is under the floor or out on the yard you will hear it. Also what another poster said shut the valve in the basement to eliminate a possible outside leak, if the usage continues you know it's leaking out there if the usage stops you can check that off the list of possibilities. Water theft is also possible since the house is vacant. Check all toilets and plumbing for flaps getting by also have the water department come and check the meter it could be malfunctioning

 

[Git]

Toilets are notorious for leaking. (literally, water down the drain)

Make a mark at the water line - inside the tank. Then turn the water off at the toilet. Give it a day or two and check to see if the water level went down inside of the tank

 

[Pen & Wrench]

If you can find the meter, and if it is somewhat "new" it may have a trickle flow indicator which would validate the leak, and might help in finding the leak. I agree, toilets often leak. I would try to check the toilet(s). If they have individual shut offs, you should be able to detect a stop in flow, or if you have the trickle indicator on the meter, you should be able to detect a slow down or stop, if you shut off the toilet(s) and the trickle stops. If the sinks have individual shut offs, I would systematically check them out by shutting them off one by one. One cup per minute is 90 gallons per day or 2,700 gallons per month, it doesn't take much. It is possible someone might be running water out of the outside hydrants. I have a friend who caught his next door neighbor red handed watering his lawn, with a hose that was connected to my friend's house. I'm not trying to accuse anyone, but I know for a fact it can and does happen. Shutting off the water should stop all leaks, if the shut off valve can be shut totally down. If you have copper plumbing, it can get pinhole leaks, but you should be able to detect moisture where it shouldn't be. I would sure be concerned about plumbing to the pool as well. You might ask the city if they have specialized equipment that would help find the leak too. Please post what you find out when you figure out what the problem is.

 

[Milton Shaw]

There are companies that specialize in finding leaks under slabs, in yards etc. It should not be much more than you are paying for water and probably sewage on that water leak. 30-40 year old copper pipe is going bad all over the place with leaks in hard to reach areas. Bite the bullet and have it located. Then decide on the fix, dig and repair or dig and relocate where it's not under slab.

 

[theundermount]

You could possibly get the service line correlated with a special machine but that's big $$ I would try to isolate different sections of the home first by process of elimination and narrow down where a leak could be. If there is plumbing to the pool I would isolate that right away and also the sprinkler system cut in a new shut off to be 100% it's isolated

Here is an example of some geophones you can listen to the pipe and hear leaks

 

[DC73]

If you can find the meter, and if it is somewhat "new" it may have a trickle flow indicator which would validate the leak, and might help in finding the leak.

I agree. The first step should be to determine if the meter has a flow indicator. If it does, turn off all water uses on the property and check the meter to see if water is still flowing.

Another item to check is the water heater. It may be losing water through a faulty pressure relief valve.

You can sometimes find water leaks under slabs and behind walls using a thermal imaging camera.

DC

 

[lbperry]

Thanks for all the replies. I’ll try to respond to as many as possible but be as brief as possible.
The only water shutoff for the house is at the curbside. The concrete enclosure contains the main valve, a meter (with a flow indicator), and what looks like the flow control solenoids? for the sprinkler system. The electronic control box for the sprinkler system is in the house.
The water company came by and basically said the flow indicator says there’s water flowing and if you’ve got everything in the house shut off there must be a leak.
A guy was supposed to come out this weekend and check to make sure the sprinkler system is completely off at the meter; all the rain we’ve had postponed that. I’m going to ask him about removing and plugging the sprinkler system connection.
All the house plumbing is under the slab.
I’ve turned off the water supply to the toilets and put food coloring in the tanks. Will check those tomorrow.
Pool company said that when they winterized the pool, they shut off all water and drained all piping.
Going to try to check out the remaining items and recheck everything else once more.
At that point, I guess it’ll be time to contact a plumbing contractor and see if he can find the leak and, if not, get the replumbing started.
I am concerned about the replumbing going into the house up through and exterior wall; and most of the drops will be coming down exterior walls. Seems like this would make it a lot more prone to freezing up than it was. Do any precautions need to be made regarding that?
Thanks Again for your help,

 

[padroo]

I would find all the shut off valves and troubleshoot by shutting each valve one at a time.

 

[lbperry]

I've shut off individual valves one at a time to see if it had any effect on the flow indicator but haven't shut them off one at a time till all I've found were off to see the total effect.
I'll try that after the guy checks the sprinkler connection.
Thanks,

 

[cgall]

We had a sudden increase in water bill, could not find evidence of leakage anywhere. Called a plumber and he had a device that detected a leak in the supply line in the front yard. He had a crew come out the next day and they excavated the pipe and replaced about 12" of it. Cost about $650 total.

 

[lbperry]

Final Chapter: House Water Leak – Long

Sorry that it has taken so long to put a period on this saga. And I appreciate all of your comments and suggestions. I have tried most of them.
Here's how it ended up: After finally getting the sprinkler system checked out I finally gave up and called the plumber. I know, I know, I should have done that to start with. Yesterday they sent out the newby team, a couple of young guys who seemed pretty knowledgeable. They spent a couple of hours checking all the usual problem areas inside the house, and trying to track down the pipe from the meter to it's entrance point at the slab, and digging up a couple of spots that looked suspicious. After not having any luck finding it they returned to base camp and sent out the A team today. After double checking much of the first teams work they brought out the electronic equipment. They used some kind of what I guess was a listening device to trace the line from the meter to the house. They finally found the leak where the pipe entered the slab at the front of the house. It was a pretty good sized leak but it had been camouflaged because it was in a shrub bed dressed with pine bark making the excess moisture spread throughout the bed. After fixing the lead and testing it they found that there was still a very minor leak that barely made the flow indicator move. The plumber said it was under the slab and if it were him he'd let it go until the water bill showed and increase. He said given where the leak likely was it was his experience that it would cost about $1500 to fix the lead in the slab. We agreed and gladly paid the $320 for his crews 5.5 hours of labor and tell the lady that's going to buy the house the situation and let her keep an eye on the water bill and make the fix if necessary.
Thanks again for all your help,