laying slate on concrete

[diy_josh]

G'day guys,

I'm currently renovating my first home. It's an old single story 80's dwelling. The front patio has those hideous orange and white tiles. They dont match the colour scheme I'm planning for the rest of the house and want to replace them with slate tiles, the broken edge type. 

My question is, once I've pulled up all the original tiles, can I lay slate straight onto the existing concrete slab? 

How do I make sure they adhere correctly? 

And what do I use to fill in the gaps?

I've seen alot of YouTube videos that mention laying sand down first. They are starting on bare soil rather then concrete.

Thanks in advance!!

[JacobZ]

Hi @diy_josh,

Welcome to the Bunnings Workshop community, it is fantastic to have you with us.

The first thing you'd do is ensure the concrete slab is perfectly flat. This can be done by grinding down high spots and filling in low spots with a floor levelling compound such as Lanko 173 Floor Leveller. 

You would then prime the surface using a product like Davco PrimeX Surface Primer to ensure it is well sealed, and the tile adhesive will stick.

To attach your tiles to the concrete, typically you would use tile adhesive that is suitable for natural stone, such Davco SMP Evo Tile Adhesive. In saying this, not all tiles are the same, so it would be best to confirm this product is suitable with the tile supplier before committing to this.

To fill the gaps between tiles, you would use Dunlop Mid Grey Wide Joint Grout, or a similar wide joint grout.

Let me know what you think and if you have further questions, please don't hesitate to ask.

Jacob