Will this take a skim

[landyandy]

This wall has been previously tiled half way up. The undercoat plaster is difficult to remove.



What are my options..

Will it skim half way and blend in

Leave the top skim on and reskim all of the wall

All plaster off and start again

Dot and dab

Thanks
Andy

 

[Alastairreid]

A tight coat of bonding over the lot then skim.

I would prime with blue grit or suchlike 1st.

 

[NickB_99]

I would prime with blue grit or suchlike 1st.

Definitely! The top part of the wall is shiny and difficult to get a physical key. The top and bottom will also behave differently with applying just diluted pva. The bottom will prob soak it quickly and the top won't.
A decent bonding agent first should make the job more straightforward.
And skim the same day after your tight coat of bonding has set.