Mogga wrote:
OK it says at least 4 weeks before painting (sealing)
but what about hanging units on them? Will they stop drying out if
there are cupboards on the walls?

And should you pva seal all romos or just bathrooms and kitchens?

No rooms at all! Never put PVA on plaster before painting; it's far
worse than not treating it at all. It seals the plaster, but makes a
nice non-stick layer which the paint will subsequently peel right off.
Use cheap diluted-down emulsion.

David