Rock waterfall platform

Aquaman7

Well-known member
Sep 15, 2019
134
NNJ
Hello,
I’m in the process of planning to install a 25,000 gallon vinyl inground pool. I will be installing a rock waterfall. Should there be a concrete slab under it? How deep should the slab be and should be reinforced with rebar?
Thanks,
Joe
 

JJ_Tex

Bronze Supporter
Jul 17, 2019
691
Prosper, TX (DFW)
Click on the link to his photos in his signature. "Pool Build - 2017 Google Photos".

Note that if you are looking at this on an iphone, the signature only appears if you turn your phone sideways.
 
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PoolGate

Gold Supporter
TFP Guide
Jun 7, 2017
4,076
Damascus, MD
No stone was used at all in my build. But my ground is very hard like total clay at that depth. My builder said there is no better base to build a pool.
 
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Aquaman7

Well-known member
Sep 15, 2019
134
NNJ
Ok. I have sandy soil. Was thinking of using 3/4” clean stone for backfill. Did you ever hear of anyone using 3/4” stone for backfill?

No stone was used at all in my build. But my ground is very hard like total clay at that depth. My builder said there is no better base to build a pool.
 

jimmythegreek

TFP Expert
Bronze Supporter
In The Industry
Aug 10, 2017
1,643
Morris Cnty NJ
You will use support tubes filled with concrete when you pour your collar. Cheap 4" drain pipe is perfect. When you pour collar put a bunch in the area you will build waterfall and cut them to height of top of wall minus 2" ahead of time and fill with concrete. Put some 2ft long pieces if rebar bent like an L in top, 2 per pier. Backfill with 3/4 stone that's the right way to backfill a pool. When you are up high enough form a pad around your piers and pour a small slab 6" thick encasing the rebar tieing it all together to the size u need. That's the only way to guarantee no pushing on wall or sinking in future. I've repaired many waterfalls on liner pools done the other way. Heavy stones and blocks near coping push down and then they push the walls out over time if not supported.
 
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Aquaman7

Well-known member
Sep 15, 2019
134
NNJ
You will use support tubes filled with concrete when you pour your collar. Cheap 4" drain pipe is perfect. When you pour collar put a bunch in the area you will build waterfall and cut them to height of top of wall minus 2" ahead of time and fill with concrete. Put some 2ft long pieces if rebar bent like an L in top, 2 per pier. Backfill with 3/4 stone that's the right way to backfill a pool. When you are up high enough form a pad around your piers and pour a small slab 6" thick encasing the rebar tieing it all together to the size u need. That's the only way to guarantee no pushing on wall or sinking in future. I've repaired many waterfalls on liner pools done the other way. Heavy stones and blocks near coping push down and then they push the walls out over time if not supported.
WOW Jimmy. I never even thought about doing it this way. Thank you so much.
I going to build the 6” slag like you said. Two questions I have is do I remove the plastic from around the piers before pouring the 6” slab? And how far away should the slab be from the pools edge?

Thanks again Jimmy
 

jimmythegreek

TFP Expert
Bronze Supporter
In The Industry
Aug 10, 2017
1,643
Morris Cnty NJ
Leave the pipe its pvc it wont rot. The slab is gonna be wherever your rock wall is gonna be I like to support all four corners if it's over 18" deep and fill the middle every 18" on center unless heavy stuff is being used. 1 bag of concrete will do 2 piers just stick in pipe when collar is wet and go back later and fill pipe after collar is dry. Keep pipe in the upper half of the collar concrete. Backfill then form up the pad. It's fine to have pad under pavers or another slab you are just making concrete table top
 

Aquaman7

Well-known member
Sep 15, 2019
134
NNJ
Jimmy you explain this very well, very detailed. Now I know how to do it. Thank you


QUOTE="jimmythegreek, post: 1745104, member: 158061"]
Leave the pipe its pvc it wont rot. The slab is gonna be wherever your rock wall is gonna be I like to support all four corners if it's over 18" deep and fill the middle every 18" on center unless heavy stuff is being used. 1 bag of concrete will do 2 piers just stick in pipe when collar is wet and go back later and fill pipe after collar is dry. Keep pipe in the upper half of the collar concrete. Backfill then form up the pad. It's fine to have pad under pavers or another slab you are just making concrete table top
[/QUOTE]