Skimming on painted plaster ?

In message , Mike writes

We had some painted walls skimmed in the old house. Don't know if he sanded it or not - but it won't do any harm will it. But he certainly PVA-ed it.

The skim was still sound a few years later when we moved.

I think I'd be just as worried on how well the paint is stuck onto the plaster below!

Probably don't need to score it. Just paint with diluted PVA, and plaster onto it when almost dry but still slightly tacky.

Obviously, the plaster can never stick better than the paint is stuck, so if the paint is coming away, then this won't work. If the chimney breast got damp from the back in the future, the paint and plaster would fall away.

Follow up.

Well it is done and all polished up. The paint was well on ( the silk finish was the bit that worried me ) and the plaster was fine, apart from it originally looking as if the wall had been part of a battleground. Thanks for replies.

Mike P