Hello.
I am in the process of scraping paint from my basement walls in a future bathroom. The plan was to remove the paint, then smooth with Ardex F5 putty, and then tile.
However, I've now discovered that the plaster, which appears to be cement-based, is strongly adhered to the hollow stone but not at all where the hollow stone is grouted. The grout is extremely porous and significantly lighter than the plaster, and now I'm wondering if anyone here has any tips on what to do. The idea that you shouldn't have stronger mortar on weaker materials could really be problematic in this case.
Thanks in advance
Newman
