..and how do you fix it in the best way? Exterior wall in a storage room in the basement, in an extension from the early '70s I believe, possibly earlier. It looks like cardboard strips unevenly distributed in the concrete, in some places the wall almost entirely consists of such strips. Someone seems to have tried plastering over it but couldn't get it to stick, the plaster easily falls off in chunks. The strips are brittle and break with the slightest handling. It's only the exterior walls that consist of this material.
It is träullit that has been used as insulation and plaster carrier, probably the moisture that has destroyed it; one needs to open up and see what is happening inside the wall..
Has any drainage been done on the house?
Has any drainage been done on the house?
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Thank you for your answer!Rejäl said:
The foundation was drained with isodrän about 7-8 years ago. But the wall in the picture faces a basement staircase on the outside, so there is air behind most of it. I have had the corresponding basement wall on the other side of the house moisture-proofed, but there was no träullit in it.
If what you have in the picture is loose and mushy, you should remove it; if it feels dry and good, you can just plaster on...N Nik Coe said:
Exactly. Wood woolite becomes brittle from long-term exposure to moisture, and what can be scraped off with your fingers isn't worth polishing but should be removed.
Then you can fill in with homemade wood woolite - take wood wool and mix it around and let it soak in a "slury" of Portland cement and water, and press it in place. Saw a piece of hardboard or similar that you can then press against so you get an even surface to polish.
Then you can fill in with homemade wood woolite - take wood wool and mix it around and let it soak in a "slury" of Portland cement and water, and press it in place. Saw a piece of hardboard or similar that you can then press against so you get an even surface to polish.