I am about to re-tile my shower cubicle and had to remove old ceramic tiles.
With the tiles removed some of the old plaster has came away exposing the
inner cement wall. The old plaster was nothing more than a scim of amout 2
to 4 mm deep. I want to fill up the voids where the cement wall is exposed
so that I have a smooth wall to work with, before applying the tile adhesive
for the new tiles.
What would be best way to do this? I am considering:
1. Re-plaster scim.
2. Fill the voids with Polyfilla or such like.
3. Fill the voids with tile grout and level & smooth off.

TIA