best way to reinstall spillover spa


Jun 5, 2015
Toronto Canada
I have had to repair my spillover for my spa 3x in 10 years
each time the mortar fails as water undermines the 5 stones
each stone is indiana ledgerock about 3-4 inches thick
with a crack of about 1/2 inch between the stones
they are laid on a bed of mortar and then grouted together in the cracks
then a thick bead of caulking is installed between the tile and the ledgerock
at present the water flows over all of the stones

I am considering making the centre stone thinner so the water goes over that one only
This will also make the water circulate better in a circle so my skimmers works better

using caulking between the stones instead of grout to make it more waterproof

what do you think

is there a special mortar to use for this purpose?

27000 gallon salt water pool with spillover and waterfall



Mod Squad
LifeTime Supporter
Jul 10, 2012
Tallahassee, FL
Can you take another picture showing the whole set up of the spa and pool? I am not sure how this is supposed to work. Does it spill over the rock all the way around the pool?


Mod Squad
LifeTime Supporter
Jul 10, 2012
Tallahassee, FL
Oh how pretty the whole pool is!!

That really helps to see what you are working with. I love the idea of doing the center one smaller. Can it be BLINGY?

@bdavis466 input please for his questions on what to use please.



TFP Expert
Platinum Supporter
Aug 4, 2014
San Clemente, CA
You and the bling🤣. Definitely not the pool for that!

The problem is the mortar being used is not intended to be submerged. As time passes the mortar weakens and loses its integrity.

If you try to drop one of the rocks to make more of a typical spillway you'd have to cut into the spa wall and will probably hit the rebar which will open a whole new set of issues.

You might want to look into Laticrete 254 and use an epoxy grout
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