Old plaster came away, render looks solid and flat what do i need to seal it with prior to tiling?

[paul cumpo]

Hi All,
Have just started removing the tiles in an old bathroom and the plaster is coming off with the old tiles but the render remains in tact and in decent condition, the surface appears to be solid, dry and flat.
Do I need to apply a primer prior to tiling? is a fairly wet room so don't want to make any errors in preparation but also on a fairly tight budget.
Added a photo of the area.
Thanks in advance for any advise.
Paul

 

[Qwerty]

Remove all plaster down to render. Brush or vacuum down, seal with an acrylic primer or SBR and then tank if required

 

[Flintstone]

Bonding coat plaster ?

 

[Dumbo]

Bonding coat plaster ?

Think you're right doesn't look like sand and cement to me

 

[Time's Ran Out]

Yes that’s just a scratch coat.
So who does what on this surface?

 

[Dumbo]

Yes that’s just a scratch coat.
So who does what on this surface?

According to a lot of adhesive manufacturer's you can't tile this as it the the first part of a 2 part system.

 

[WetSaw]

Depends on what is going on it. Skim it, overboard, so many choices!

 

[paul cumpo]

yeah it could be a first skim of plaster, ideally wanted to seal it then tile straight onto it, would have been there years.

 

[WetSaw]

Regardless of how long it's been there you can't tile onto bonding.

 

[paul cumpo]

so am I better applying a thin top coat to it before plastering or do I need to remove it all and board, assuming the 2nd one is the most costly