My 1st Job Skim, Patch Or Board?

[Jon W]

This is my bathroom wall after taking a few tiles to see what lurks beneath. The top surface of the plaster has come off quite easily so I presume this will be the case when I take the rest off. I want to know what is the best prep before I start tiling. I'm not planning on tiling everywhere so don't want the extra depth that boards will add. I also can't really afford the time it takes for a plaster skim to dry. Is it OK to use a sand /cement /waterproofing agent to flatten the surface?

 

[White Room]

Is that base material a sand/cement or a soft gypsum plaster base???

 

[Jon W]

I don't know. How can I tell?

 

[Andy Allen]

Try poking a nail in it....s/c will be a lot harder..

 

[Jon W]

Does this help? It seems quite pocked and fairly hard but don't know how old it is.

 

[p4ulo]

Looks like original sand/cement render.
TBH I would get it skimmed mate, so much easier to work off and complete confidence, minimal build-up will match the rest of your walls thicknesses too....DO IT!