Newbie With Old Concrete Pool - Help!

[oldconcretepool]

I re did the waterline tiles 2 years ago but upon opening found that many of the top most tiles popped off. After looking behind the tile I see that there is a pretty clear horizontal crack between the coping and the beam/wall. I tiled over this crack last time and I didn't fill the crack and believe either moisture or shifting between the two surfaces popped the tile. To fix this correctly I was thinking of only attaching the tile with epoxy on the wall below the crack and either not using any adhesive above the crack or maybe using silicone so it will flex if things move/shift. So my questions are: 1) should I fill this crack with anything and if so what?; 2) If you recommend filling the crack can I then tile over this and not worry about shifting or moisture? As additional information, I did re-caulk the expansion joint between the deck and coping - it was a little 'tired' and could have allowed moisture under the coping.

[txpoolguy]

Much depends on where you live. Moisture and shifting do cause a lot of damage like this, and it's also common to see this kind of damage in Springtime, after freezing conditions during winter. The earth shifts, causing small cracks, then moisture gets into the cracks, freezes and expands, causing tile to pop off, coping to lift, and sometimes damage to the beam of the pool. It's difficult to seal permanently. I'd recommend you have a professional come and look at it to recommend the best solution for your region.

[4serendipity]

In this situation the culprit is usually the coping itself. The tile band popping off is the sympton of the problem and the coping will need to be removed and repoured. Then you can re-mud and tile the perimiter and expect lasting results.

I hope this information is helpful.

S.