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If the original lime plaster isn’t blown and the surface can be stabilised there’s no reason it can’t be skimmed over.
Knocking it all off is a filthy job.
absurdbird-
Tricky to estimate how filthy it will be just to get down to the plaster. Personally I couldn't leave the wallpaper on and any method that gets that paper off damages the plaster underneath so you have the repairs to that then I would put lining paper on it because it's a hallway.
Massive job whichever way you look at it.
Like I said though, builders would knock it all off and render or pb. I have done work like this in a more decorative fashion but you have to ask yourself by the end whether it's worth it. Of course it's a decision that you wouldn't make based on a couple of internet photos.
Airhead
Unlucky. That's a lot of work however you approach it. Time wise it would probably be better to strip the whole lot off plaster included and start again from bricks or stud with new plasterboard or render and plaster, that's what a builder would do.
Just estimating the alternative in time and materials and it's a lot. Is it possibly 'Artex' since that was used to cover all manner of problems.