Is my house settling, or do I have foundation problems?

Some background of the place...
I live in the north Texas area, DFW specifically. I've lived in the house for a couple years now, but it was built back in 1972. The foundation is a simple slab, however the house sits up on a small hill.

The original owner of the house had a second story addition put on it after it was built on one side of the house (above the garage). This of course caused sinking and they hired an engineer and subsequently hired a foundation company (Olshan) to come out and install piers to support the structure. The work carries a lifetime warranty that was transferred to me also.

I've been lately noticing some cracks in the walls and ceiling areas on multiple areas of the house, not just the side that had the piers installed. Sometimes I think perhaps they've always been there and I just haven't noticed, but I'm not so sure anymore. I'd rather be safe than sorry.

Is there anything I can do to examine if the foundation is maintaining a proper level, or should I just get an engineer out to look it over? Is the house just settling? I do have the name and number of the original engineer who did the work after the addition at least.

 

What do you have as flooring that is covering the slab, around the perimeter of the house?

If it is carpeted, it be a little harder to tell, but you might notice something...and you'd SURE notice it if severe enough. To get a rough idea without peelign back the carpet, if that is what yo have, you could try to lay a straight aedge acrtoss the slab, along the walls, and see if there are humps or valleys in it, especially under where you see cracks. You may even consider pulling back the carpet, if it is carpeted, to have a look.


If you have no cracks, it be doubtful you have problems with the slab/foundation. But if you see cracks...OFFSET cracks... where the cement is higher on one side of the crack than the other...you have problems. And I wouldn't doubt that is what you will find.

(But I hope not.)

 

Mark the cracks and check them every few weeks to see if they get longer.

 

So there he stands...marking...going, "Yep!, they sure are getting loooooon!!!!" (as his voice trails off)... as he and his house get swallowed up into a sink hole! You here of these things.

 

The crack got worse in less than 6 hours???
Get the hell out of the house....

 

Measuring cracks, especially in the short term (less than one year) can be difficult and can end up in a guessing game.

If you look on the web, you should be able to find crack gages or plastic you attach to the concrete. They may be found at the sites that sell home inspection equipment. These allow you to get a more accurate measure that is important when you are trying to determine if the crack is active or inactive.

If you feel the crack is active, consult with a structural engineer for confirmation and corrective measures.

Dick

 

You guys are on highly expansive soils in that area, and have been suffering through drought conditions. You should probably get soaker hose and water your foundation on a regular basis.

 

I'm not sure if it's due to getting too much rain recently or not enough?

Oh well, I have arranged for a civil engineer to do a complete foundation inspection next week. I don't know what I'm doing when it comes to this and as I said, I'd rather be safe than sorry. I'll try to remember to post the results after the appointment.

 

A preliminary update...

Well the engineer came out today and did some extensive tests to diagnose the health of the foundation. I'll get a detailed report next week, but the bottom line is that it does need some minor repair.

On one side of the house which already has had piers installed, one pier, possibly two, needs to be adjusted as there was a difference of about 1" between two adjacent rooms on that side of the house. In addition they pointed out a spot they suggested I try and fill in with additional soil and create some sort of drainage since that particular spot would tend to hold water during the rain.

On the other side of the house, the engineer noticed that over a span of about 25', there was another 1" difference. I'm not certain what the suggested remedy for that side will be since that side is not piered.

The engineer suggested that there might be a very slow sewage leak as the cause. I explained that before I purchased the place that I had the previous owners run a leak test. They had the foundation company's plumbing division run a test and in their report they believed that there was a sewage leak somewhere under the house. The owner called in another contractor for a second opinion. That contractor could find no leak. Both used the same method to test for a sewage leak by plugging the sewer cleanout and filling a shower and observing for about 5 minutes.

The engineer still suggested getting another plumber out to run a leak test. I hardly see what good it would do to run another test, but given that there is some differential between the levels of the house, it might indicate that the first plumbing report was correct. The only problem I have with that is the report indicated the leak was somewhere under the house, meaning under the slab. That's just great...how in the world would they locate the leak then?

Overall though the engineer said the foundation was in good health for its age, it just needs a little maintenance work done on it.

Any suggestions on the sewage leak? I can't imagine how much it would cost for someone to even try to locate the leak.

 

By what method did the first plumber, and then the second plumber plug the clean out line? Actually, they would have had to have plugged it down in the line below where the clean out is.

They may have to send in a camera to take a look to see if they see anything.

Or perhaps they could inflate a device and send it in the line at various points while filling water behind it, to see at what point the water disappears at. Then pull out the device and keep track of the footage of it down the line.

Or putting the line under some presure, depending on the drain material, and listening by sound equipment. Stethoscope.

Or drilling small holes in the concrete floor and probing for moisture, and digging up where the worst moisture/pooling is.

Or calling in a "water witch" or dowser.

 

I'm uncertain how they plugged the clean-out but for some reason I want to say they inflated a device and used that method.

Supposing that the sewer repair company did send in some sort of robotic camera and did spot a small leak, how would they be able to repair it? Does the robot also include welding equipment?

 

At least they'd feel a little more confident as to where to start digging up your cement floor.

 

I have one follow-up question. I checked the report again made by the one plumbing company that said they did spot a small sewage leak. One the comments they stated "need to replace one way c/o in order to do isolation" c/o = clean-out I'm sure. They also gave a price quote for how much to put in a new clean-out and isolation. The quote also indicates they'd use a camera to locate the leak I'm assuming.

My question is what is the difference between a one-way clean-out and others? Do you know what type they would most likely replace it with?

Some other details on this report include that my sewage pipes are cast iron in fair condition and the clean-out is a single leading to the city's lines, the depth being about 18".

 

To the best of my knowledge, what one would call a one-way cleanout would be in a y-configuration...where a two-way cleanout would be a straight tee enabling a snake to go both directions if need be.

You said you assume they will use a camera? I would never assume anything, in this life. Especially if anything costs big dollars.

Now suppose there is this SMALL leak as claimed. Perhaps the small leak has nothing to do with your problem, if say your soil is sand with good drainage and is away from the foundation transition area where your problem is. I would be reluctant to have someone simply fix such a SMALL (what classifies as small?) leak for big bucks, if it wasn't really the contributing problem, let's say. I would venture to say that all over the country, there are under slab/underground (small)sewer leaks going on all the time with no bad side effects, due to the joinery at the various sections.

Anything to do with plumbing, coupled with digging and concrete work = big money.