CMU pool without liner questions (edited)

[RussMaGuss]

Plaster needs to be laid down in one day and then, depending on the plaster type, the pool needs to be filled within a few hours of the final troweling (if aggregate exposure is required then sometimes the plaster is left overnight and the exposure is done the following morning). If it’s left for days before filling, the plaster will not properly cure and the lack of carbonate exposure from the water will not allow the plaster chemistry to happen. You risk creating a porous and weak plaster that will likely fail well before 15-20 years. You will also create lots of “cold joints” between the plaster layers which will ultimately affect appearance. This is why I suggested that you save money elsewhere in the project and not skimp on the plaster job. Paying a crew of experienced plaster applicators $8k-$12k (depends on your area) to do the job right and get you the longest possible plaster life (along with whatever warranty they’re willing to give for an unconventional pool structure) is worth it. And you save yourself days of back breaking labor hauling around mud and troweling plaster.

I honestly think you’d be much better off with a liner pool. Given your location in a cold northern mid-west climate, plaster is not really an optimal surface.

Yeah I think you’re right. Will go on the lookout for a liner company to field measure (I don’t have any steps, but I always hear measuring to get those things just right is a pain.) Or I’ll put on redgaurd, hydroban, etc and tile it, if I can find a decent tile.

Thanks everyone for the input. Hopefully if anyone else in the future has this idea they can find this thread useful!

 

[JamesW]

The design is basically like a retaining wall and you can look at retaining wall design, engineering and architecture plans to get an idea about creating a wall that can withstand the lateral pressure and force without moving or cracking.

 

[flynwill]

FWIW my Sister and Brother-in-Law built a CMU pool many years ago, it's a free-form shape with a plaster finish. And indeed he had to reference retaining wall engineering when designing the structure. He built the CMU himself, but the I believe hired a contractor to install the plaster finish. That pool is now ~30 years old and still in good shape.

But yes this is Southern California where plastered concrete pools are the norm.

 

[ajw22]

Or I’ll put on redgaurd, hydroban, etc and tile it, if I can find a decent tile.

I think tile will give you more problems then all the terrible things @JoyfulNoise can lay on you about plaster.

With tile you have the problem of maintaining the grout lines. If you are in an area that gets freeze/thaw cycles in the winter then any crack in the grout will let water get behind tiles and the freeze thaw cycle will loosen tiles, pop them off, or crack them.

Liner pools have their own issues with liners getting brittle and developing cracks, tearing, popping out of the liner track, or water getting behind the liner.

Each pool surface has its pros and cons. Plaster is my preferred surface after owning plaster pools for 30+ years.

 

[RussMaGuss]

I think tile will give you more problems then all the terrible things @JoyfulNoise can lay on you about plaster.

With tile you have the problem of maintaining the grout lines. If you are in an area that gets freeze/thaw cycles in the winter then any crack in the grout will let water get behind tiles and the freeze thaw cycle will loosen tiles, pop them off, or crack them.

Liner pools have their own issues with liners getting brittle and developing cracks, tearing, popping out of the liner track, or water getting behind the liner.

Each pool surface has its pros and cons. Plaster is my preferred surface after owning plaster pools for 30+ years.

I wonder how tile pools hold up here with epoxy based grouts. I imagine they would be ok. If not, maybe I'll shift my focus back onto assembling a 1 day crew to do the plastering then. I immediately was thinking if I did tile: How would I properly winterize it? Would I want to run a submersible heating element all winter long to prevent ice from blowing out tiles at the water line? There's got to be exterior tile pools around here that have held up for a long time, right? Maybe some kind of pool safe anti-freeze additive

 

[ajw22]

I wonder how tile pools hold up here with epoxy based grouts. I imagine they would be ok.

Epoxy based grouts are no more flexible than regular grout.

If not, maybe I'll shift my focus back onto assembling a 1 day crew to do the plastering then. I immediately was thinking if I did tile: How would I properly winterize it? Would I want to run a submersible heating element all winter long to prevent ice from blowing out tiles at the water line? There's got to be exterior tile pools around here that have held up for a long time, right? Maybe some kind of pool safe anti-freeze additive

I think you will find tiled pools in commercial properties where money is less of a concern.

I see commercial outdoor pools being winterized by draining them completely, covering the pool, and then on opening cleaning the pool before filling. Tile would work if you commit to that.

 

[RussMaGuss]

Epoxy based grouts are no more flexible than regular grout.


I think you will find tiled pools in commercial properties where money is less of a concern.

I see commercial outdoor pools being winterized by draining them completely, covering the pool, and then on opening cleaning the pool before filling. Tile would work if you commit to that.

I always heard there’s risk of cracking pools by fully draining them from the earth pushing against the walls and leaving that the whole winter. As long as there is water in there, it keeps the lateral pressure in check. I am going to put a couple pilasters in to counteract anything, would that be enough? Planning to backfill with sand or ca6/ca7 gravel (screenings). I imagine my design going 6’ deep on all the walls too keep the whole shell as a full height beam would keep everything super strong, so if draining it would be an ok way to winterize it, it wouldn’t be an issue. I have a well for water that does not have much hardness and is easy to treat, so that’s not much if any of an expense

 

[ajw22]

I always heard there’s risk of cracking pools by fully draining them from the earth pushing against the walls and leaving that the whole winter.

Never heard of a rebar/gunite pool walls collapsing from the earth pressure.

Empty pools do pop out of the ground if there is upward pressure from ground water. So empty pools should have hydrostatic drains opened in the floor to relieve water pressures.

 

[RussMaGuss]

Never heard of a rebar/gunite pool walls collapsing from the earth pressure.

Empty pools do pop out of the ground if there is upward pressure from ground water. So empty pools should have hydrostatic drains opened in the floor to relieve water pressures.

Well that’s reassuring, thanks! Was thinking about maybe even putting in a sump around the exterior footer. Maybe overkill but also probably not a bad idea. Don’t really have drainage issues on the land

 

[phonedave]

I wonder how tile pools hold up here with epoxy based grouts. I imagine they would be ok. If not, maybe I'll shift my focus back onto assembling a 1 day crew to do the plastering then. I immediately was thinking if I did tile: How would I properly winterize it? Would I want to run a submersible heating element all winter long to prevent ice from blowing out tiles at the water line? There's got to be exterior tile pools around here that have held up for a long time, right? Maybe some kind of pool safe anti-freeze additive

The right tile and the right material.

Impervious / non-porous tile (glass). Perhaps an all epoxy system. Even heard of leaving some key points in the tile ungrouted to allow for movement.

 

[MAPR-Austin]

I've only seen a few CMU pools and they were all liner pools. I would not give any warranty if I plastered one, I think you would end up with cracks - I just can't see it being as strong as a monolithic structure. The plaster may be considered watertight but it is just a veneer which any crack will radiate through.

In my opinion a liner is the way to go for you. Mason experience aside it is a totally different skillset to plaster a pool and have it look passable let alone good. You would not want your first time to be on a pool with just you and a helper.

 

[RussMaGuss]

I've only seen a few CMU pools and they were all liner pools. I would not give any warranty if I plastered one, I think you would end up with cracks - I just can't see it being as strong as a monolithic structure. The plaster may be considered watertight but it is just a veneer which any crack will radiate through.

In my opinion a liner is the way to go for you. Mason experience aside it is a totally different skillset to plaster a pool and have it look passable let alone good. You would not want your first time to be on a pool with just you and a helper.

Yeah, definitely veering towards tile. I think $1/sqft of hydro ban, a 3x6 tile, and waterproof grout will be the way to go. That way I can take several days instead of 1 day, and it’ll last a super long time.

Just need to pick out a tile that’s not a $10/sqft fancy mosaic—I’ll save that for the waterline lol

 

[RussMaGuss]

The right tile and the right material.

Impervious / non-porous tile (glass). Perhaps an all epoxy system. Even heard of leaving some key points in the tile ungrouted to allow for movement.

Yeah, expansion joints aren’t a bad idea, maybe 1 in the middle going the full length and 1 in the middle going across the width. Waterproof membrane aside it’ll still provide excellent crack resistance

 

[RussMaGuss]

Hi all,

I had a thread going a few weeks back about my CMU pool build. I had ultimately decided on a full tile finish, but now after doing more research I am back on the fence. I am wondering about the longevity/ pros and cons of the tile vs a rubberized paint finish. I was looking into "sider-crete" but not one single person has updated about their pool finish after a few years so I have zero confidence in that kind of product as of now.

If I go the tile route, I plan to:
-hydroban, redgard etc to waterproof the shell first
-tile using "ocean mosaics" tile (3/4"x3/4" with 1/8" grout lines approx) These come in sheets about 12x12" I think
-use laticrete platinum 254 mortar
-use mapei ultracolor plus FA grout

If I go the rubber paint route, I plan to:
-do a stucco spray coat on the CMU and concrete floor
-paint according to manufacture's specs


My estimated cost to do full tile since I'm doing it with myself and my laborer is around $7,400
waterproofing $1,000
tile $4,500
mortar $500
grout $600
laborer for 3-4 days @ $25/hr cash

My estimated cost to do stucco and paint is around $2,500

I have no hang-ups on cost for either, my main concern is longevity/maintenance. If the rubber paint pool needs to be re-coated every few years that's not a big deal. I am on well water and it's basically free to drain and refill. After doing more research I am wondering how long the tile finish will actually last though. I am well versed in tile and with my helper the pool should only take a few days to set tile and grout. Online articles about full tile pools seem all over the spectrum. Some are saying they will last forever and others are saying maybe only 10 years. If I do full tile and can get 50 years out of it I would go that route easily VS re-painting the walls/floor every few years


Any input is appreciated!
-Russ

 

[Toxophilite]

Kind of an difficult question, as it's more to a person's taste than need for utility. If cost is not the issue, it's more a question not unlike what is better to have, a Lamborghini or a Ford Focus? Longevity plays, but not on the choice of two that far apart on the spectrum of aesthetics. If your cost estimate is correct for tile, the decision is made in my book.

 

[mknauss]

@Flying Tivo is one fully tiled pool that I know of. Let's see if they can give you some advice.

 

[RussMaGuss]

As long as my estimate for sqft is right, it should be right there since all my labor is "free" and no overhead/profit, so everything besides my laborer's wages is at-cost. If this were for a customer however.... lol

 

[Flying Tivo]

If I go the tile route, I plan to:
-hydroban, redgard etc to waterproof the shell first
-tile using "ocean mosaics" tile (3/4"x3/4" with 1/8" grout lines approx) These come in sheets about 12x12" I think
-use laticrete platinum 254 mortar
-use mapei ultracolor plus FA grout

You should stick completely to the Laticrete system, they give extended warranty if used in a system. That is what i have and wont look back. Not a single tile has popped, 5 years this May. I dont see a need for extra wide grout for expansion, but i dont have freezing weather, nor that white stuff you get up north.
Hydroban
Platinum 254
Spectralock Pro
The tile itself does not play much, but make sure is quality.
Installer experience is a must, ask directly if they have experience with laticrete systems, or call laticrete to give you local installers info.

 

[kimkats]

I am in to watch this one!

 

[Newdude]

@Flying Tivo got any pics ? While tile might not be the best choice for Russ, many of us here consider your pool to be the gold standard of what a pool *could* look like.

If I go the rubber paint route, I plan to:

Every once in a while the thought of using a plasti-dip or rhino liner type application comes up and it always fails the sniff test with those materials not being well tested for pools. Nobody has any idea what will leach off of them in a pool environment.