What type of foam board on new pool

[redraider2007]

I am planning to use foam for my pool bottom instead of sand and would like to get some thoughts on what foam board to use. It seems that from past discussion on this site and others there is no consistent answer on going with the white foam board or blue/pink (at lowes it is blue and home depot it is pink) board.

It seems to me that the blue/pink would be more durable and a bit more flexible, however if anyone has any input on that I would love to hear it.

Also, I am thinking if I go with the blue/pink I would go 1/2" thick, if going with the white I would go 1".

Are there any thoughts on using the foam board in the link below? I would think if you did two layers of this it would result in a quicker install, less tape and less potential visible lines.

https://www.lowes.com/pd/Kingspan-I...d-Polystyrene-Foam-Board-Insulation/999972970

Thank you all for the help and educational discussion!

 

[scout123]

I saw that at Lowes, and yes it would be easier imo, but it didn't feel all that cushiony (I don't think that's a word, but you know what I mean! LOL) I ended up with the 4x8 polystyrene foam board, and i want to say it was 3/4 inch thick or maybe 1 inch. It feels really nice on the feet.


Edit: I just reread that you will use 2 layers. That might work out better. Honestly, I didn't even think of that. I know the single layer just didn't feel thick enough to me, but I didn't think to double it over and then feel of it.

 

[Jamison04]

You really want to go with an extruded foam and not an expanded varied. The expanded can absorb moisture and degrade where as the extruded type is solid through out, ie it doesn't consist of tiny foam beads smushed together.

We used the blue stuff from Lowe's. It is 3/4" thick and has tongue and groove edges. 2 years ago it was around $15 a panel.

 

[redraider2007]

Thanks for the information!

Is this the product you used from Lowe’s? (I hope the picture shows up, this is my first time to upload a picture and I am trying it from my phone)

 

[DaneCE]

Just make sure that it is extruded polystyrene and not expanded polystyrene.

example: Shop Kingspan Insulation (Common: 0.75-in x 4-ft x 8-ft; Actual: 0.75-in x 4-ft x 8-ft) R4 Unfaced Polystyrene Foam Board Insulation at Lowes.com

 

[Jamison04]

Thanks for the information!

Is this the product you used from Lowe’s? (I hope the picture shows up, this is my first time to upload a picture and I am trying it from my phone)

That isn't it. It was made by DOW. I have been searching online but I can't find it at Lowe's now. I'm able to find the Owen's Corning brand at home depot. It is pink extruded foam also with tongue and groove edges.

Mainly you want to choose a foam panel that is dense and looks like solid foam which is called extruded foam. The stuff that looks like a Styrofoam cooler (tiny foam pellets smushed together look) isn't what you would want to go with for longevity purposes.

The DOW foam board we used or even the Owen's corning stuff from home depot is rated for ground contact, and can be used for foundation and footing insulation. So that is why the extruded form is pushed on here to use over the basic Styrofoam panels.

I can't figure out how to post a pic now that all the photo sites have killed off third party linking. Otherwise I would snap a pic of a piece we had left over.