How do I install natural slate in a inground swimming pool.?
what type of grout do I use underwater in a swimming pool.
do you have any photos of a natural broken slte swimming pool.
Answers:
It's a very expensive proposition. First, you'll need the cooperation of a specialized pool contractor and also tile contractor- and both need to know what is being built and cooperate as best as they are able. The substrate- what the slate will adhere to is either going to have to be somewhat flexible or extra rigid- as a tile person I cannot say which.
As for the tile mortar, regular polyblend white or grey should be fine- they are both rated for uderwater even though material safety data sheets do not reflect this. You will need many gallons of the flex additive, which can also be diluted with White Lightning brand 40 year caulk. Alternately you can use epoxy mortar, but this is EXTREMELY expensive. There is such a thing as underwater mortar that you can replace a tile even while under water, but it and also the expoxy harden within a minute or so.
Once you have installed all of your slate you will want to make sure it has cured for at least 3 days, and cover your pool with a tarp.
After that, if you use real slate (and I recommend ceramic tile for this project- for cost, durability and underwater reasons) then I suggest you paint Mop n Glo (or similar LOW GRADE janitorial wax over entire slate preferably with paint brush, like white washing a fence. Do not over coat.
Next grout the thing. Use Cat 5 rated grout (commercial grade). I like the Grey with slate. Hint: You're not going to keep it white, although you could use white for some trim outside of the actual water areas.
Once it is grouted you will notice that the Mop n Glo kept so much of the grout from seeping into the porous slate. Also, it will be mostly etched off already, as long as you used low grade stuff. You will need muriatic acid solution with hand scrubbers, working from top down, scrubbing the walls of all excess grout and wax, rinsing, etc. This will require a pump to remove standing water at the bottom, and the crew will need someone dedicated to rinsing, sqeegying (sp?) and using a hose to remove waste water, and this must be done carefully and consistently all the way throughout the entire washing process.
Eventually when the walls are done and the curves to the bottom are done you will be able to use a floor scrubbing machine on the bottom. Make sure the crew understands the importance of not dropping the machine, chipping the edges, etc.
Once the entire thing is scrubbed clean, rinsed clean, then let it cure for a couple of days. By this time you're going to already have some puddles of water and they should be clean. Start hosing it down, make sure to backwash your filter plenty of times, and eventually once it's filled up= Enjoy! You got your self the neighborhood's most expensive pool!
I did one for the band REM and also one for Ted Turner in Atlanta many years ago. I have no idea where the pictures are. Also did something similar that was featured in the Atlanta Journal's decorator's showhouse but it was not actually underwater 100% of time, more of a cascading fountain type thing. Hope this helps!
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