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[scitrek]

Hi all

I have a wall where large(ish) chunks of what I think is a first layer of plaster (down to a paper layer) have come off when removing items attached with adhesive strips. The wall sounds hollow so I think it's plasterboard. Upon inspection, the edges of the "holes" were just as detached, basically like a whole surface layer was coming off the wall, so I scraped it off until all the edges of the area seem solidly attached (see photos). I now have a few questions:

1. Is this indeed a surface layer of plaster, down to the paper?
2. What could have caused it to detach (to avoid in the future)?
3. What's the best course of action to treat the area and level it with the rest of the wall? PVA then replaster and feather?
4. Should I (not sure how) test for other areas of the wall where the surface is detaching? I wouldn't want to repaint the whole wall and have this happen again...

One more thing, I noticed some prominent cracks in the wall (not sure what they're due to), when removing the surface layer it carried with it whatever material had been used to fill the crack (see photo 3). Is it possible this is due to a flexible, rubbery material being used instead of a solid one? Is that the best choice to fill this?

Thanks a lot!

[stoneyboy]

Hi scitrek,
You will need to confirm what the base material is before trying to get the surface right.
From your pictures I would suspect that you have masonry walls that have been plastered and this has detached from the wall giving the hollow sound you describe.
Try digging into the surface and see what you find.
Regards S

[scitrek]

Hi Stoneyboy, thanks for your reply. A few more details:

- The house is (AFAIK) a 1930s terraced
- The wall is a 1st floor internal wall, separating a bedroom from the hallway
- I've drilled a hole and used an endoscope to look inside, from what I can see it looks like a hollow wall made of wood slats, with a layer of plaster on top. The hole is "hairy", which makes me think this might be an original wall with horse hair mixed in with the plaster?

[scitrek]

Quick update: I've ended up just dusting and wiping the surface with a wet sponge, then applied "Ronseal Smooth Finish Filler Multi-Purpose Ready Mixed", with which I had great results in the past. It adhered really well and I was able to smooth the transition to existing paint layer perfectly (see image). I think once painted it will be perfect, and this repair seems actually much stronger than the existing surface.