Level on clay soil

[Nathan8372]

I can relate to the clay. Very frustrating here as well. Seeing as that you have equipment, cutting down a bit might be a great option, not just for the base but to avert the stubborn nutgrass and such we get. Then spray an herbicide killer and/or place a liner down for future weeds. And yes, some folks use pea gravel as it tends to gel together better and create a firmer/tighter base. You see others use sand, but depending on the soil and moment around/under the pool, sand can begin to seep-out (or down through cracks) and become useless. Once you have the pea gravel down, you can still toss some insulation pads, Gorilla pads, or something to go between that and the liner if you want that extra cushion for your feet. Hope that helps.

@Texas Splash I'm down here in Corpus where we have 'Victoria clay' soil. I'm excavating a 2' deep hole for our new, semi in ground pool - any advice on what to do about the pavers at each column? Should I use the pea gravel or just dig in and put the pavers? Thank you!

 

[Texas Splash]

Should I use the pea gravel or just dig in and put the pavers? Thank you!

For pool supporting posts, you should be fine with just setting the pavers on a flat level surface as long as the stones are wide enough to disperse weight and not sink. Tamp the ground well to make it firm. 12 x 12 pavers are very popular, and some even go with 18 x 18. While probably not necessary, you could dig-down 3-4 inches and use a base material if you believe the clay is prone to significant cracking and the paver stone may shift over time. Limestone is a popular base in my area. Be sure the pavers are flush with the ground so the liner doesn't get pinched by a paver edge unless you are using some insulation pads or something that would increase the height of the flooring to be level with the stone. Good luck!

 

[Nathan8372]

For pool supporting posts, you should be fine with just setting the pavers on a flat level surface as long as the stones are wide enough to disperse weight and not sink. Tamp the ground well to make it firm. 12 x 12 pavers are very popular, and some even go with 18 x 18. While probably not necessary, you could dig-down 3-4 inches and use a base material if you believe the clay is prone to significant cracking and the paver stone may shift over time. Limestone is a popular base in my area. Be sure the pavers are flush with the ground so the liner doesn't get pinched by a paver edge unless you are using some insulation pads or something that would increase the height of the flooring to be level with the stone. Good luck!

Hey thanks for your answer! We are digging 2' down and I plan on leveling the base, installing 12x12 pavers at each column then using sand as the base. I think we are going to use the foam cove and then BACKFILL with screened topsoil instead of the Victoria clay. Does this sound right to you?

 

[Texas Splash]

Sounds like you have a good path forward. Take lots of photos of your install. Might be helpful to others later. Have some aspirin ready. Good luck!

 

[merc123]

I got all mine done with a screened top soil but it had quite a bit of clay in it. I put a few buckets down (I have a tractor) and smoothed it with a 2x4x10. Once that was done I ran over it with a tractor and packed it down. Then I set it and rode over it again and again until I didn't leave tire marks any more. Process took a while and definitely not tractor rental worthy. I actually had to build an area up almost 1' and pack it down. So far no sagging and it's been a year.

 

[Nathan8372]

I got all mine done with a screened top soil but it had quite a bit of clay in it. I put a few buckets down (I have a tractor) and smoothed it with a 2x4x10. Once that was done I ran over it with a tractor and packed it down. Then I set it and rode over it again and again until I didn't leave tire marks any more. Process took a while and definitely not tractor rental worthy. I actually had to build an area up almost 1' and pack it down. So far no sagging and it's been a year.

I'm actually considering backfilling with concrete slurry, partly due to the manufacturer recommendation (HII) and the fact that it would hold less moisture than the soil. Any thoughts?

 

[merc123]

I'm actually considering backfilling with concrete slurry, partly due to the manufacturer recommendation (HII) and the fact that it would hold less moisture than the soil. Any thoughts?

So long as it packs I'd say it'll be fine. The issue with top soil is that it usually contains organic matter that breaks down over time causing settling. The slurry probably won't break down.

 

[Nathan8372]

Sounds like you have a good path forward. Take lots of photos of your install. Might be helpful to others later. Have some aspirin ready. Good luck!

What are you thoughts on putting crushed granite under each concrete paver block? Any experience with them sinking in clay after heavy rain?

 

[Texas Splash]

What are you thoughts on putting crushed granite under each concrete paver block? Any experience with them sinking in clay after heavy rain?

Certainly can't hurt. As you know, once our clay gets saturated it's a total mess. If a paver shifts and tilts, it will dig-in even more so a gravel base might help.