painting over mixed new and old plaster

[AlF2008]

We've had some plastering done to repair the walls where the original plaster was blown and also to a badly plastered-over fireplace. We've let it dry out and its about to get painted. I've washed down the old plaster with sugar soap to get rid of the old paste.

I know we should put a mist coat on the fresh plaster. What about the old plaster? Should it get a coat of the same? I'm presuming it wont do any harm...

All advice gratefully received.

 

[Robbie uk]

It wont do any harm at all to give it all a mist coat. This will show any imperfections in the plaster and these can be filled etc prior to final coating.

 

[AlF2008]

Great. thanks for the reply!