Lime or something else

[Callismichael]

Hi there

Please can somebody help with identifying whether this is lime plaster or something else?

I have a 1930 stone built property and the walls are very smooth in places. There was wallpaper over the walls.

Now there is clear gypsum in other parts of the property but if you look at the 1st image those are the walls and second is the ceiling. If I were to scratch it it feels very hard.

I have tried the vinegar test and it does foz more than portland but I'm still not convinced.

I just don't want to go to the expense and limitation of lime plaster where needed for walls in bad condition if it isn't a breathable house anyway.

Thank you in advance
Michael

 

[RBailey]

It’s not always required to hack of everything and re-plaster.
What are the problem areas, damp, blown plaster, high ground levels etc.
I’d target new lime plaster at the problem areas.