This side conversation has been split off of this topic. JasonLion
Ok, I really don't get something here...why are you putting foam board under the bottom support rails? Foam board will not support the weight of the wall on a rail. You should be putting the foam on the inside of the bottom rails, not under them. Basically a big circle the size of the inside area of the bottom rails.
A permanent above ground pool is not anything like an intex pool. People do this stuff with intex pools because there is no support outside of the footings. The bottom rails support the wall just as much as the bottom plates. If you look at Casey's install she has pavers even under the middle area of the bottom rails. That is considered overkill, but by far only helps support them as much as possible, so there is no issue doing that, especially if you had to fill the area and the fill was not compacted or was compacted with sandy soil, then you most certainly have to do what Casey did.
My point is foam board is not able to support the rails. You really have to sink the pavers to ground level and put the foam board on the inside of the bottom rails. I am doing just that on my install, just that I will have a base of limestone so I don't need pavers, but I am going with 1.5" thick foam board and that will be a giant circle inside the bottom rails.
Even though it could be argued that the bases on the pavers will take all the weight, but it also creates singular points of stress on the wall as well. The rails having less "solid" support doesn't mean it doesn't get spread over a wider area.
I removed an all-resin pool that basically had a couple of lower rails broken because they didn't have enough support under them and you could tell the wall was buckled between where it happened on the support bases that had pavers.
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Just wanted to say you are definitely doing everything else right and by the numbers though... Good work so far...