I am making a shower plinth with celcon blocks This will be capped with ply to take the tray. I intend to tile flush to the underside of the tray on the plinth face. I will leave the plinth 9mm short of the edge of the shower base to allow tiles to be flush. Could I stick this row of tiles directly to the blocks or would I need to render.

render would be best ! would not take to long to do and you will get a better fix . make sure you sbr prime the render .ok

I could easily render it but was concerned about the effects on the support at the edge of the tray. I suppose though render is supportive.

thats right !!

Dot and dab a bit of plasterboard on to it

As above, I would dry line, those blocks can be weak and start cracking with very little movement

i have screwed and plugged hardibacker to it never had any probs

those are thermolight block and would probably dry the adhesive out to quickly

I think you are right David. When I laid them as a base i brushed plenty of water on first. I have set them back to allow me to get a 6mm board on.

Easy T

dont use plaster board any where near a shower base . if water gets to it the tiles will let go as it is not water proof. use backer board if you are going to line it

Thanks Paul. I will be.

Originally Posted by paul flight

dont use plaster board any where near a shower base . if water gets to it the tiles will let go as it is not water proof. use backer board if you are going to line it

It you tile it properly plasterboard will not be a problem

Originally Posted by Scottley

It you tile it properly plasterboard will not be a problem

In this situation Scottley agree with you. I will use a 6mm backing board as I need a small amount anyway to cover an existing pipe box out to align with a shallow wall build out to accommodate the new shower basin.

Easy T

If i had hardi id use that but nothing wrong with plasteboard. Its been used in untanked situations for years. Not all fail.

With the newer tanking product then its the way forward obviously