hidden underneath problem??

Hello,

I have a slab foundation house in central Alabama that was built in the mid 1960's. Our lot is level and has never flooded. When this sub-division was built it was outside the city limits. It is now inside the limits. I've lived in it for 23 years. I've just gotten divorced and been approved for a new loan on the house.

This is not a new problem. When I walk down the hall it seems to me there is one part that has something I can only describe as a hollow sound. Kind of like going up concrete football stands or some steps. Not a ringing sound but it is the only location in the house where this occurs.

This would be about where the sewage line would run under the slab. We have never been aware of any odor to the house.

A while back (when I was already aware of this sound) a waste pipe in the a wall (opposite bathroom wall from hall) had to be repaired. When they took out sheetrock looking for the source of the leak I was able to see under the tub. I guess it is/was normal for the area around the hole in the slab for the tub drain to be a large square filled in with sand. Well, the sand was there. I'm just thinking IF there is a sewage line break that it does not appear to be happening at the tub.

Could this be a sewage line leak that is causing sand/dirt under slab to 'shrink' and leave a pocket?

Is there a way to check this myself with no or very little expense?

If I have to call someone in to check for a possible leak, what kind of costs might I have?

If repairs have to be made, what would be done and what possible costs might there be?

Is this anything that could be filled to home owner's insurance? Any problems/consequences there?

Thank you for your time and any suggestions.
bamakodaker

 

Put your hand on the spot where the hollow sound is. Does it feel colder than it does a 5 or 6 feet away?

 

Ahhhh you caught me!! I thought I'd put down everything that needed to be considered - except that I have the slab covered with a layer of foam then carpet! Can't feel the concrete!
bama

 

Put your hand there anyway. If the concrete is colder, the carpet would be colder too.

 

You could have a camera run down the sewer line and get a video recording of the inside of the pipe. That would tell you if there were any gross breaks in the line but it might not tell you if there were some rather small leaks at any fittings. The cost for this would likely be in the neighborhood of $100 to $300.

 

I tried, honestly. Spent time crawling around on hands and knees. The heat and humidity are already up in Alabama. A/C's been on all day. The carpet all feels the same. I tried the vinyl flooring close to that hollow sound, comparing to further away. Still can't tell any difference.

Hmmm, new thought. If there is a leak - would the sound be different just after back to back showers, washing dishes and clothes versus coming home after house been empty all day?

bama

 

I know not all plumbers do this so what should I look for in phone book and such as I look for this type service?

bama

 

I don't think that you will hear any difference in the sound.