My pool was completed in Aug of 2008. The builder also did the concrete deck. I knew nothing about pools or pool construction so the fact that the guy didn't seal the expansion joint wasn't something I looked for. Long story short, the deck has settled about 1.25" in two spots which is shifting the skimmer so a leak has been caused (he actually fixed this twice in previous summers when the deck had settled only a .25", he never mentioned the joint seal). I'm telling him he didn't properly tamp the soil and that's why the deck has settled and NOW he says it's because I didn't seal the joint and water has caused sub-erosion. I'm saying that's his responsibility to seal the joint. Why would he not do that? Is that common practice? All there was was some foam. And how do I know that the unsealed joint was the cause of the problem and it wasn't the water leaking around the skimmer? It's been 5yrs since the pool was built and wondering if anyone else has experienced a similar problem and if I have a case since he never sealed the joint.