yes, a plaster skim and emulsion question

[Gille]

Can I just check I have the right approach to painting a new ceiling and
skimmed walls. The ceiling is skim over plasterboard, the walls are skim
over original old plaster and in some areas skim over patches of bonding.

I have bought Dulux trade supermatt white (not vinyl matt)
I plan to give a mist coat (diluted about 30-40%)
Rub down and any filling that is needed
Then a second coat (diluted about 15-20%)
Light sand
Then a third coat (diluted about 15-20%)
Job done (hopefully)

Does this seem the best approach. A daft question this, but what grade of
sandpaper is best to use on the mist coat and in between other coats.

Cheers

 

[spice]

Before you paint, I would lightly rub down the plaster, as it may look smooth to the eye, but there will be little nibs all over it, they look like tiny pin heads, and would show up in the artificial light.

As to the filling, you will probably have to fill trowel marks and the odd goude or nick, so you only need a light fill.
After you have rubbed down the filled bits, and before you actually roll your next coat, I would get the paint brush and dip it into your watered down paint, and brush on the filled bits, perhaps a couple of times, this will stop the filler from bleeding through when you apply your subsequent coats.