House is 1920’s brick with lathe/plaster walls; some sort of thick texture layer is on living room walls, stairwell and second floor hall walls, as well as ceilings. My main problem is the appearance over the last few years of several cracks and small “bubbles” where the texture layer has separated from underlying plaster.

(First time trying Imgur link, bear w me here!)

I’m really concerned about

further deterioration of this layer and

whether it reflects moisture ingress from the outside either focally or in general and

how to best address it - to repair/patch it (biggest defect is at the corner of a window) and meep doing that every couple of years?

what IS this stuff? Is lead or asbestos a worry?

I dislike the look- and the texture itself varies from wall to wall and there’s the odd obvious old patch visible. But can live with it.A contractor said the most cost effective (vs removal vs adding drywall) way to get rid of the fake stucco whatever plus stabilize the surface is lamination of the surface. Some added layer(s)??? It’s very costly ($30k for LR and stairwell) and I can’t find much of anything about it on Reddit or by searching.

TLDR: 100-yr-old brick/lathe/plaster walls’ thick texture has random cracks, a few progressing to loose pieces. Significance? Fixes?

Wall texture layer separating from old plaster