How to lay tiles on cracked concrete slab?

[livefreeandroam]

 

I'm repairing some tiles around the pool area where the slab has crack and lifted slightly (a few mm). I've removed the tiles and ground the concrete so it's flush across the crack. (See image). Now I'm getting ready to tile, but I'm not sure of a few things.

My questions...

1. How to fill the crack in the slab? I was going to use filler rod with Maxisil Pool Silicon sealant. Is that the right method? Should I open the crack a little wider?

2. What tile adhesive offers good flex?

3. Can I lay new tiles across the crack or should I cut them to follow the crack?

4. Finally, what is recommended for the grout?

[EricL]

Hello @livefreeandroam 

Welcome to the Bunnings Workshop community. It's sensational to have you join us, and thanks for sharing your question about your tiles. 

By filling the crack in the slab, it should stop water from flowing in and causing it to shift. I suggest using the gap filler rod and your choice of silicone sealant. For the tile adhesive, I suggest using Davco 20kg Ultraflex Ceramic Tile Adhesive. Using the Ultraflex tile adhesive you should be able to lay the tile down without having to cut or split it. I recommend using Dunlop 1.5kg Flexible Coloured Grout. My best advice is to seal the grout with CPC 220ml Shower Plug Sealant to prevent water from entering through the grout.

If you need further assistance, please let us know.

Eric

[livefreeandroam]

Thank you, Eric.

I can now proceed with this little project.

Kindly,

Matt.

[livefreeandroam]

FWIW, the silicone I'm using is:

Maxisil Pool Silicone 

[MitchellMc]

Hi @livefreeandroam,

The Maxisil Pool Silicone would be better for use inside the pool. For structural cracks, we'd typically use Sikaflex 11FC, a polyurethane rather than a silicone.

Mitchell