If you have expansive clay soil, nothing that occurs as a result of it will be the builder's responsibility in most cases.

It is a problem with your lot, not the house.

And 'hairline' cracks even in a properly designed and installed slab is considered quite normal.

Unless you can prove by a soil engineer's anaylysis of the ground and by a structural engineer's analysis of the house that the builder was negligent in constructing the house on expansive clay soil, there is little you can do but use a different type of flooring.

I din't know California rules and methods.
I can't see the cracks from here.

But many hairline cracks are indeed normal and may be more from shrinkage than from foundation movement.

To assess your individdual problem, you need an experienced contractor or - better - an independent experienced home inspector. This would be your nickle as it would be your burden of proof if you believe you have been wronged by the builder.

You probably have nothing to be concerned about and shrinkage cracks only that can be regrouted. However, if the tiles themselves are cracked, this may indicate foundation movement. I will disagree with the previous poster on this. A builder should not place a foundation directly on expansive soils. By trenching and replacing with good gravel and drainage, he can re-engineer the site before building to avoid problems. Your builder may have scrimped on this step.

Thank you all for the inputs.

The cracks are indeed on the tiles. The grouts in between are good, except at the bottom of the shower stall where grouts usualy crack. I forgot to mention these tiles are around the tub and on the shower wall.

I thought however they prepared the soil for other lots, they also did for mine. My lot elevation is a little higher on this street. None of my neighbors have this problem. All houses in this development are on post tension slabs.

I think you should pursue this then. It is definitely not normal for any ceramic tiles to crack when properly installed over a sound substrate. It might not be the foundation but maybe something else in the framing methods or other problems but the cracks in the tiles themselves are not normal. the builder shouyld be getting his tile man to follow up and fix it.

We live in Texas and our home is 7 & 1/2 years old. Last year, we suspected foundation issues and contacted our builder to inspect it (bc it's still under warranty until our ten year mark). The contractor inspected our home and said that all our cracks and separation are ok and our foundation was not a concern. Since then, our neighbors (three houses down) have had their foundation repaired (driveway and lawn completely dug up) and today, our immediate next door neighbor started the same process. Very deep holes dug along the side of the house that I could see, entire front yard dug up and driveway gone. Should this be cause for alarm bc they are in such close proximity? Both us and our neighbors have always used soaker hoses, but obviously that didn't prevent their foundation issues. Any suggestions?

You have to get the cracks repaired preventing it from cracking further before installing back the tiles. Epoxy will be the best product.