Fiberglass pool leveling

[BC78]

We recently had a fiberglass pool installed. I was curious of the install as I'm in construction too and had watched a bunch of pool install videos just to attempt to partially educate myself on whats "normal" but there were no install videos of fiberglass Pools in sand in high water table areas. The install went pretty much like the videos but they required 6 posts 3 on each side to be installed under the pool lip to keep the pool level whilst filing with water and back wash sand around the pool. Now the back washing def compacted the sand nicely around the pool as it was filling but the support posts don't get cut off and are left in place. My concern is that the lounge deck on the shallow end of the pool is not an easy place to get the sand to wash under but it feels mostly solid but the shallow end is about 1/2" higher than the deep end due to the weight of the water in the deep end making the pool sink a little more. First off what's an acceptable amount of out of level between the 2 long ends and would it be a good idea to cut these temp wooden support posts out in case they cause issues in the future with the pool settling?

 

[bradgray]

Welcome!

I'm not an installer unfortunately so I can't offer much by way of helpful advice.

But I do have sympathy because we have dozens of fiberglass pools and every one that has a sundeck/shamu experiences bowing/settling/hollowing under the ledge.

It may be there is an industry-accepted tolerance that you and I wouldn't generally accept due to the logistical challenge of that backfill.

There are installers on this forum so hopefully they'll chime in soon!

 

[BC78]

That is a concern. Currently it’s accessible to backwash more sand under it so I may dig up the sand and attempt to get it back washed some more before the concrete goes in.

 

[Texas Splash]

My Viking installation manual states for the pool to be set within 1/2" of level, but I believe other references give slightly different variances based on the length of the pool. You might check with your pool manufacture. Not sure the posts will hamper anything if left in other than perhaps rotting away in the future.

 

[TX2OBX]

So from a similar experience with this. Its 100% sand where I am. We had the same issue. They didnt recommend gravel where I am as it eventually just washes away leaving voids so fresh fill sand was brought in and compacted like a dozen times then the pool set. After the pool was initially set it was gradually filled (sand side and water). This gave fill sand a chance to compact then another layer of sand, fill the pool another 6 inches or so, etc and that was done until the pool was eventually filled.

For the tanning ledge we had the same issue. PB ended up using those same metal ties like you see on telephone poles on the shallow end/tanning ledge side to level it out. Then set the tanning ledge and spa in a liquidly concrete "flowable fill" I believe was the term. This flowable fill was mainly to help avoid voids under the spa and tanning ledge, def super solid there, but I guess it also helped "lock" the pool in with those tie downs. But funny enough PB kept it weighed down with a bunch of buckets full of water until the deck was set. Pool is pretty level but also only about 6 months old. will see how it lasts.