House flooding from nowhere?

[jinman]

My daughter has a problem. Her two-story house is flooding downstairs, but neither she nor the plumber can find a leak. The meter shows no flow whatsoever with the house pressurized. We ran all the showers, sink drains, washing machine, and toilets. Nothing caused any leaks. Her carpet is soaked and now pulled back away from the wall where the water is coming from. I did not mention the dishwasher in the list above because after running the dishwasher, the water will start to seep out from the wall in the area below the water heater which is upstairs. The dishwasher is about 12 feet away from where the water starts to seep out from under the baseboard. There's one other thing, the floor beside the dishwasher is very warm. It's tile on top of a concrete slab. I walked across it in my stocking feet and it was very warm.

There are two possibilities that I can think could cause this problem. One is that the diswasher drain is clogged and water is being pumped up and out the drain vent. I know this should show up on the roof, but I'm thinking that it might tie into the emergency vent for her water heater. I've even considered that her water heater might be overpressured and lifting the emergency vent. If that vent is not sealed properly, it could be leaking.

Anytime I feel a warm slab, I think of hot water pooling under the slab. I'm also thinking that if the drain is broken and water is going under the slab, hydrostatic pressure might be pushing water up through any opening in the slab like around a drain line or water pipe entering the house. These are all in the walls and water would show up along the baseboards. So far, that's what is happening and no walls are wet or damaged.

My daughter's insurance company is sending out someone who can do ultrasonic scans to find leaks. I would expect they might also be able to map the source of the hot floor, but I don't know.

What does the TBN braintrust think? This is a head-scratcher for me.

 

[dex3361]

Some insurance companies have Infrared cameras that you can see the hot or cold area from moisture. Its a pricey tool but can help in such searches. It sounds as though you might be on the right track with the dishwasher.

 

[beenthere]

Possibly a pipe in a wall that froze and cracked? Notice you've been getting some cold air in TX.

 

[dave1949]

Jinman,

If the hot water tank relief is opening, you should be able to feel that pipe warm up or hear water running. Maybe you could watch for that while running the dishwasher. But, if that is the cause, other hot water demands should cause the same to happen, not just the dishwasher.

That the water appears at a wall base, could mean the water originates under the slab. The wall may be anchored with ramset shots, lag bolts, etc. These could provide an 'escape' path for water under pressure.

I picture dishwasher pumps as pretty wimpy things. I don't know if they have the capacity to push water very far up a vent pipe.

Good luck.
Dave.

 

[Bird]

When you mentioned water seeping out from a baseboard, I first wondered if it might be the same problem our daughter had with her two story house last summer. The builder finally decided the problem was a bricklayer who failed to leave the weep holes in the bottom course of bricks. Sounded weird to me, but they removed the bottom course of bricks and re-did that, with weep holes, and so far no more problem. Of course they also re-painted inside, replaced carpet, etc. But I don't think your daughter's problem will be the same.

 

[jinman]

Randall: I think that's the device they are using, but it's actually a high-tech plumber instead of the insurance company that owns the machine.

Beenthere: None of these pipes are on outside walls and all inside walls have never been below 60 degrees during our coldest weather. I guess it's possible, but I don't think probable.

Dave: That's exactly right about the water heater emergency vent. I was trying to explain that over the phone to my daughter and SIL last night, but I don't think they fully understood what I was saying. They didn't even know there was an emergency pressure relief or a cutoff valve on the cold water line above the heater until I told them about it. Like so many kids these days, they don't have a clue how some of the simplest things work. My daughter knew she had a warm floor, but it wasn't until I told her it normally indicates a water leak below the slab that she even considered it more than a curiosity. I'm beginning to believe that we should offer a class in college on home ownership and the basics of how things work in your home.

Bird: I walked around the house and every brick in the first tier has condensation drains on each side of the brick. The bricks are vented very well. I went around with the plumber who was checking to make sure there was no place where dirt added to a flowerbed was up over the first tier of brick. This water is definitely not coming from there. I also had my son-in-law crawl up into his attic with a flashlight and check all the vent stacks to look for water running down from the roof. With the snow we've had lately, I wanted to make sure the vent stacks weren't letting water seep by the seal and run down the pipe. All the attic is dry, so that's not the source either.

BTW: The washing machine seems to drain normally with no backups or leaks from it; however, it's about 15 feet away from from the dishwasher near the garage and may be on a different drain that wouldn't normally back feed into the diswasher drain.

 

[MF1455v]

Good luck on that one Jim. I have a similar puzzle just before we moved from our house in Georgetown. Luckily it was contained to the garage.

The garage was about 3 feet lower that the rest of the house, with a sink and water softener against the wall. The wall was concrete for that 3 feet. I bumped the wall with the edge of a shelf and water started running out of the wall. First I thought I had hit a water line but it stopped after about 10 gallons was on the garage floor. I could run water in any drain on that wall and here would come the water again. After doing some exploratory surgery with my hammer drill on chisel I found the issue. There was a drain line fitting end flush with the edge of the wall. It had duct tape over the end and then mortared over. The duct tape had held for 10 years until I bumped and tore it. It was even lower that the septic line leaving the house so it had to fill before anything would leave the house. What a mess.

James

 

[JB4310]

Having trouble getting a good picture of what the problem is your describing.

But I'll just take some wild guesses. Where ever copper water pipes go thru concrete they are vulnerable to deterioration and possible leaking. It sounds like maybe there are lines under the floor going to the dishwasher? though you said the meter was not moving.

In your case seems you narrowed it down to something with that DW, either feed lines or drain line. Another thought, is there a washing machine drain in that vicinity, most of the drain system is closed but where that washer dumps into the drain it's usually a loose fit, so if there is a slow draining system it can back up out of there.

I have seen on many occasions water leaking in basements from water service lines, meter does not move because it is leaking before the meter right where the line comes thru the foundation wall, usually on the outside and the water goes down under the footing and pushes up on the floor.

Curious what you find. JB.

 

[Bird]

Like so many kids these days, they don't have a clue how some of the simplest things work.

Yep, I learned some of those things the hard way myself. And I'll never forget a niece calling me one morning to ask for my help with a copper water line in their attic that had frozen and burst. Fortunately, it was an easy one to get to both ends and replace, but someone had told her husband you had to heat those sweated joints to get them apart, so he had used up a whole box of kitchen matches trying to heat it before they called me.

Jim, you didn't mention how old this house is, did you? I had an aunt and uncle in Dallas many years ago with the main water line coming into the house being copper in or under the concrete slab. When it deteriorated and leaked, the plumber cut it off outside the house and ran a line up into the attic to bring the water in. But of course that wasn't warm water and they could hear water running under the house.

We bought a new house in 1977 and only a month or so later, while I was out of town, my wife noticed a tiny bit of water coming out from the bottom of an interior wall and called the builder. They found a sweated copper joint leaking in that wall and repaired it.

I have seen on many occasions water leaking in basements from water service lines, meter does not move because it is leaking before the meter right where the line comes thru the foundation wall, usually on the outside and the water goes down under the footing and pushes up on the floor.

JB, I understand that (and bet Jim does, too) because I did gas leakage surveys up north where meters were frequently in the basement, but most folks down here have never seen such. The houses are on a concrete slab, so there's no basement and no meter under the house.

 

[dave1949]

Yep, I learned some of those things the hard way myself. And I'll never forget a niece calling me one morning to ask for my help with a copper water line in their attic that had frozen and burst. Fortunately, it was an easy one to get to both ends and replace, but someone had told her husband you had to heat those sweated joints to get them apart, so he had used up a whole box of kitchen matches trying to heat it before they called me.

That's just too funny! He gets an A for effort at least. Glad he didn't burn down the house.

I was thinking these days, with an internet connection, you can find a write-up or video on how to do just about any home maintenance task. Or an explanation of how things work. So much info at your fingertips these days it's truly incredible.

Kids are all different, some wade in where angels fear to tread and others don't really want to get hands-on. I am guessing any homeowner-type classes in high school would get a pretty good draw of students even as an elective. Unfortunately, many schools just don't offer those types of classes anymore.

In my previous life as a shop teacher, I offered a class on basic auto care. Real simple things like change a tire, light bulbs, wipers, check/change fluids, battery care, etc. It was always well attended, over half were girls. I had two old junkers that still ran enough for my purposes- nobody could mess up their own cars. I would guide them through doing something on their own vehicles if they needed to. They had no desire to become mechanics of course, but it was a confidence builder for kids whose father's never take the time to teach the basics.
Dave.