Replace Grouting?

[zcb]

The grouting directly under the coping tiles is coming loose in places. I was told I could apply a silicone sealant over the grouting. Will this work?

[PartyPool]

I have the same problem. I did some reading and think it's because of the ground around the pool moving and cracking the grout and popping the tiles off. The last few years I would lose maybe 6 or 7 tiles a year, and I would put them back up with silicone grout I got at Home Depot (I forget the brand, but it said "Marine" on it). However, the tiles I put back up would not stay up. Plus I was losing more tiles - last winter was brutal for some reason, and I lost over 50 tiles.

I have put the tiles back on this May with a product I found called E-Z Patch (http://www.e-zpatch.com). It's a flexible mortar/grout specifically for pools. It's much more expensive than the stuff at Home Depot, but it works really well, plus you can buy a clean-up product that you can use to wipe off the excess really easily. It has only been a month or so, but I have not lost any tiles.

The argument for the silicone-flexible grout is that it will flex with temperature changes and earth movement. Concrete/thin-set is brittle and will crack if anything flexes.

One caveat: I ground off the old grout and thin-set to make room for the new grout and to start with a clean surface. All the ground-up concrete/thin-set/grout dust got into my water. And now I can't get it out (see my post "Get Fine Dust Out of My Pool!"). And it might have damaged my sand filter. Ugh!

[Safrole Jay]

I'll share my woes, which raise two concerns: the seal between coping and deck and the water hardness.

I did not appreciate the function of the deck/coping seal, but it keeps water off your beam that will later freeze the ground around it and pop off your tiles. I was losing tiles like crazy but was ignorant about the cause. I ponied up $300 for two kits of Deck-O-Seal and got it all taken care of. I removed all the old sealant with a die grinder, then I used a funnel and dry sand to fill the voids up to a half inch from the deck/coping interface. Using a stiff nail brush to whisk the sand away makes the process a lot quicker. It makes the sand smooth and exposes the sidewalls of both structures - a nice, even, square channel ready for the nastiest goop you can imagine. And definitely use a two-part polysulfide sealant. They say nothing else lasts. It's the same stuff they use to seal the rivets in airplanes, but you have to get it online or from a concrete supplier. I used the pourable viscosity. Even xylene won't really clean it up. I ended up grinding off a couple little spills. (dog footprints)

But I also noticed that my grout was disappearing faster than my grandpa's gumline. Evidently my water hardness was too low, and hungry water will pull calcium out of the masonry - eating it right up. I had to regrout all 125' of my waterline tile. UGH!! That and rebuilding some of the coping bed took over 30 hours.

I used the polymer-modified (flexible) mortar from Menard's for both cement and grout. I don't use marble dust anymore. They told me it is supposed to keep the mix from shrinking when it cures, but I had a widespread failure. Two sections were just falling off and upon checking, the cement was so weak you could put a screwdriver into it with little effort, like it was sandstone. Maybe it was a bad bag of mortar, maybe the soft water attacked it, or maybe we didn't adequately mix the marble and mortar - but in any event I wanted to reduce a variable so I nixed it. Some of my new bonds survived one winter and all seem good.

[dagger]

I had the same problem about the grout on top of the tiles but below the deck falling out. I used this product and applied with a caulking gun. Works great. It opened a very little bit in the second year after application but hardly noticable.

http://www.e-zpatch.com/gallery2.htm#E-Z_Patch®_22__

E-Z Patch® 22

Neutral Cure 100% Silicone Rubber

Available in 10.3 oz. cartridges

Off-White or clear color

See Coverage Chart Below

View training video for this product

Our same neutral cure formula for ceramic tile adhesion/grout and other sealant uses. Low odor, UV stable, mildew resistant, and non-corrosive. Excellent bonding to cured masonry surfaces, ceramic tile, fiberglass, wood, fiber optics, and ABS glass. Our white color is low gloss and off white to match regular white cement tile grout. Available in off white and clear colors.

E-Z Patch® 22

Price $20.02

10.3 oz. cartridges, for ceramic tile adhesion/grout and other sealant uses. Off white.

Quantity

Clear

Quantity

[gandan]

I use a product called Billy Doo which is an epoxy type adhesive which can be used to restick the small tiles back on withouthout draining the pool, I just cant figure out why the tiles are comng off. I have just bought(January) the house in spain which is six years old and everything was great until the last two months . I am getting patches of two and four tiles coming away in various parts of the poo and cant figure out why. The Bily Doo is great but costs 14 euros a pack and only does about 10 -12 small glass tiles. Any advice would be appreciated. I thnk the company is called bzc.co.uk if that helps anyone. Brilliant stuff, cures underwater in less than 24hrs, but be quick applying it.

[Seahunt]

So what should the hardness be at to prevent this from happening? It started happening on my pool and I raised it from 170 to 220.

Thanks.

I'll share my woes, which raise two concerns: the seal between coping and deck and the water hardness.

I did not appreciate the function of the deck/coping seal, but it keeps water off your beam that will later freeze the ground around it and pop off your tiles. I was losing tiles like crazy but was ignorant about the cause. I ponied up $300 for two kits of Deck-O-Seal and got it all taken care of. I removed all the old sealant with a die grinder, then I used a funnel and dry sand to fill the voids up to a half inch from the deck/coping interface. Using a stiff nail brush to whisk the sand away makes the process a lot quicker. It makes the sand smooth and exposes the sidewalls of both structures - a nice, even, square channel ready for the nastiest goop you can imagine. And definitely use a two-part polysulfide sealant. They say nothing else lasts. It's the same stuff they use to seal the rivets in airplanes, but you have to get it online or from a concrete supplier. I used the pourable viscosity. Even xylene won't really clean it up. I ended up grinding off a couple little spills. (dog footprints)

But I also noticed that my grout was disappearing faster than my grandpa's gumline. Evidently my water hardness was too low, and hungry water will pull calcium out of the masonry - eating it right up. I had to regrout all 125' of my waterline tile. UGH!! That and rebuilding some of the coping bed took over 30 hours.

I used the polymer-modified (flexible) mortar from Menard's for both cement and grout. I don't use marble dust anymore. They told me it is supposed to keep the mix from shrinking when it cures, but I had a widespread failure. Two sections were just falling off and upon checking, the cement was so weak you could put a screwdriver into it with little effort, like it was sandstone. Maybe it was a bad bag of mortar, maybe the soft water attacked it, or maybe we didn't adequately mix the marble and mortar - but in any event I wanted to reduce a variable so I nixed it. Some of my new bonds survived one winter and all seem good.

[thomasderb]

I've been having the same problem with a gunite/pebble tech pool - I'm losing tile directly below the concrete deck - there is a fine crack behind the tile and sand is coming out.

Was the pool built incorrectly ?

[wiirwin]

I've been having the same problem with a gunite/pebble tech pool - I'm losing tile directly below the concrete deck - there is a fine crack behind the tile and sand is coming out.

Was the pool built incorrectly ?

[wiirwin]

I am having the same issue too. I think it is from the settling of the building and pool and the water robbing the calcium from the structure because it seems to need calcium. I also noticed some bad rust stains in the pebble tec which I am having difficulty getting out. I read the thing about the calcium in earlier strands. I actually put 10 lbs in the last two days and the stains look better and I can see all the way to the bottom of my pool. It is so clean and clear.