Best method for repairing joint between coping and tile

[CarolinaCamper]

I have a 1970s-built pool that has held up surprisingly well, but the grout (or whatever it is) between the coping and tile is deteriorating in places. I have been researching what the best thing is to use to repair it and am getting all kinds of different answers. One place said sanded grout with some kind of additive to make it usable in a wet environment. My pool guy who has been in the business since the 60s said I should use white Portland cement mixed 1:1 with marble dust. And I found a thread on here that said to use deck-o-seal or sikaflex (sp). This is a project we CAN do ourselves, but I don't understand the difference between these different methods and if there are benefits of one over the other. Can anyone shed some light on it?

 

[Bperry]

I have a 1970s-built pool that has held up surprisingly well, but the grout (or whatever it is) between the coping and tile is deteriorating in places. I have been researching what the best thing is to use to repair it and am getting all kinds of different answers. One place said sanded grout with some kind of additive to make it usable in a wet environment. My pool guy who has been in the business since the 60s said I should use white Portland cement mixed 1:1 with marble dust. And I found a thread on here that said to use deck-o-seal or sikaflex (sp). This is a project we CAN do ourselves, but I don't understand the difference between these different methods and if there are benefits of one over the other. Can anyone shed some light on it?

What type of coping and decking do you have? The answer depends on that. If the coping is separate from the decking, then it should be bonded to the pool “bond beam” and then you can use any wet environment grout. If the deck is cantilever style, then you need to keep an expansion joint between those items and so a flexible sealant is needed.

 

[CarolinaCamper]

What type of coping and decking do you have? The answer depends on that. If the coping is separate from the decking, then it should be bonded to the pool “bond beam” and then you can use any wet environment grout. If the deck is cantilever style, then you need to keep an expansion joint between those items and so a flexible sealant is needed.

Thanks - The deck and coping are separate.

 

[Bperry]

Thanks - The deck and coping are separate.

As long as there’s an expansion joint between the coping and the deck, you should be able to use sanded grout at the tiles. I’m assuming it’s supposed to be rated for underwater use, but I’m not sure. I used the same thin set for grout that I used to bond the tiles to the wall. But then I demo’ed all the tiles but that’s another story.