Kevin Brady wrote:
I have a downstairs loo in a side building attached to the house,
which I'm doing up.

Internal wall is brickwork with a light coat of white emulsion over
(very light coat in places, you can see brick through the brush
strokes). The ceiling is a in-situ concrete, with tiny ridges where
the forming timbers were removed. The ceiling is similarly treated to
a watery emuslion finish.

Ideally I would like to give both surfaces a skimcoat of (bonding?)
plaster. Do I first need to remove the watery paint from the
bricks/concrete? Is bonding plaster the best for skimming (2 coats
max)?

Many thanks.

On brickwork its ok and probably wont need a pva bond.