We remodeled our pool last summer, and about 20% of the waterlines tiles have already cracked! Needless to say, we are not happy. The pool remodeling company we used seems to be declining to honor their 5 year warranty. (Keeps giving me the run around, and always has an excuse why they can't fix it right now, but check back in a few months.) We have gotten 2 other opinions so far, with totally different recommendations and explanations about what went wrong, so I am very confused. We don't want to throw good money after bad, so I am looking for opinions from anyone who has seen a similar problem.

Relevant details: The pool was probably originally built in the late 80s, but we are not sure the exact age. We are in the DFW area in Texas, and our area commonly has expansive clay soil and a few light freezes, but people normally keep the pools open all winter. We do NOT have a SWG. The cracks are horizontal and mostly are about an inch above where the water usually is, and seem clustered in the two ends of the pool. The concrete pool deck was in good condition last year (no cracks), so we just had it recoated by Sundek. We have cantilever coping, which is basically part of our deck, and it was in good condition so that was not replaced. We did replace the plaster with a pebble finish, which seems ok so far. The tile is a 6x6 which was sold by a company that only sells pool tile.

The material between the tile and the coping is a brittle grout-like material, and I think maybe it should have been flexible mastic instead, but I am not 100% sure. This material has been flaking out in large chunks since about 3 months after the reno was complete, but the tile was fine at that point. In the spring, we noticed that many of the tiles had cracked over the winter.

The original remodeling company has vaguely agreed to replace the expansion joint with mastic, and replace the cracked tiles, but has been delaying when they can do it for 9 months now, always has a reason it can't be done soon, but perhaps in the future. I am thinking of just having it fixed by another company, and going after the original company for a refund.

I've had two companies out to give a repair bid. The first company thought it was that the mortarbed wasn't mixed properly, and the tile would ALL have to come out and be entirely replaced, and would offer a warranty on that job, but was very expensive. The second company thought that it was just how the soil around our pool was and it was likely to crack again if reinstalled... he was willing to replace the tiles, but seemed to think we should just live with the cracks, as it would probably happen again. This guy said the expansion joint was the wrong material and should be replaced, but that was not likely what caused the tile cracking... he emphasized I had two separate problems going on.

Does anyone here have an idea what is going on? Anyone had a similar issue? I am so confused since I've gotten such different professional opinions. I surely don't want to shell out big bucks to fix it, only to find that we didn't address the actual problem and it cracks again next year!