Tip for polymer wall pool builders

[JohnnyG66]

We built a polymer walled pool last year (DIY) and got to the point of installing the liner, filling it to about 2/3, and backfilling. Then it was covered for the winter. Last Fall, I watched a video from "Swimming Pool Steve" where he mentioned liner coping failure on some polymer wall pools. This was after I had installed the liner, but it really resonated with me as I recalled wondering how well the screws that came with the coping - which were intended for steel walls - would grip the polymer. About 3.4 through the coping install (coping is "cantilevered" and attached to the side of the walls), I started pre-drilling holes in the aluminum coping as I had a feeling that the screw was tightening up against the coping itself instead of the wall. I also used bolts and nuts in a few places where the screw had obviously stripped the polymer. After watching that video, I put a dab of construction adhesive on each coping screw on the outside of the wall hoping it would add some extra insurance.

Now after taking the cover off and inspecting things, I see that indeed, the coping has started to pull away in a few places! I think the glue helped prevent complete failure, at least. Since I haven't poured the collar for the coping stone yet, I have an opportunity to fix it properly. Plan is to drop the liner at each screw (pool is currently about 1/2 full) and replace it with stainless bolts, nuts and washers. Also, there is one section where expansion/contraction has 2 ends of coping forcing against each other. I'll have to carefully trim this with an oscillating tool.

Moral of the story - if you're building a polymer wall pool and especially if using cantilevered style coping, toss the included screws and use stainless bolts, nuts, and washers instead. Also, leave about 2 millimeter gap between coping pieces for expansion/contraction.

 

[JohnnyG66]

...which leads to a question. Any tips on how to get the liner unhooked from the coping? I tried hot water and then a heat gun, along with a plunger to stretch it - no dice so far. Just can't get enough slack. Maybe just not getting it warm enough? Seems to cool pretty quickly.

 

[JohnnyG66]

Got the liner out of the track. Was quite easy with more sun, but especially rubber gloves (in my case, rubber coated fabric). The rubber gloves helped provide enough grip to pull the liner up, and a small screwdriver was used to coax the bead out. I pulled out about 2 foot sections at a time, removing the original screws and replacing with 5mm stainless bolts, washer, and locking nuts. Took about 3.5 hours to do one 36' side.

While doing this, I discovered that the top-most plastic fastener at every panel joint had snapped over the winter. So here's another tip for polymer wall pool builds - do not use the plastic fasteners at panel joints! Use galvanized or stainless bolts, washers and nuts. The plastic fasteners are fine for attaching the supports mid-panel.