Remodeling home and found slab crack

[Agk007]

Hello everyone, i'm a first time home buyer, and learning all the joys of home ownership. We are in the process of remodeling the inside of the home and we ripped up the carpet in one room and found a crack in the foundation that only is in the corner that i or the inspector didn't notice outside. I noticed the crack has signs of moisture so water seems to be getting a bit. I put a level on the crack and its a tad bit higher on one side, but i don't really have any cracks in the drywall. My house is two stories and i have noticed a tiny vertical hairline crack upstairs in the bedroom above the window generally in the same area of the corner that is cracked, but after investigating i found its where two pieces of sheetrock are butted together and it wasn't taped properly. The inspector did make note of the crack and said he didn't recommend any foundation repairs at this time, but he also didnt see the crack under the carpet as it doesnt look as bad outside. My question to you guys is, should i be worried about this crack? Should i wait and see if it moves from time to time? I feel somewhat glad that the crack is isolated to the corner, but the corner does support part of the wall upstairs and downstairs. I'm not very familiar with foundation issues, but i am watering my foundation twice a week as i live in Arlington Texas where clay soil is everywhere. My foundation is a post-tension slab-on-grade.
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[nealtw]

Post-tension slab-on-grade is only talked about up here, but you can be sure the whole system was engineered. Up here an engineer can be held responsible for 30 years.

 

[havasu]

That is common in Southern California homes.

 

[Chris]

My house is full of those cracks. Around here that is more than normal.

 

[nealtw]

This does look like normal cracks found in concrete but it would be nice to here from someone that knows about post tension slabs.

 

[BridgeMan]

I know next-to-nothing about post-tensioned slabs, but I do have some concrete repair experience. If it were mine, I'd dribble some low-modulus, low viscosity epoxy into the crack. And then watch it over time. If the epoxy cracks, then you know it's a moving crack, and more serious corrective measures may be needed.

Next step would then be to consult a local engineer familiar with post-tensioned slabs and how best to repair them.

 

[Agk007]

Thanks everyone, glad to know it's not that bad, I will keep an eye on it though to see if it moves. Mainly I'm concerned with the moisture getting in since we are about to buy new carpet. Thanks again though!

 

[nealtw]

Concrete cracked or not will not prevent moisture from getting in, you rely on the perimiter drain and foundation waterproofing for that.