Can I skim coat a painted interior concrete block wall? If so, with what & how?
Is the wall dry? is the paint in good condition? If it is dry you could use joint compound. If the paint is pealing it would need to be scraped first. I like using mortar on block walls because it holds up to moisture better than joint compound but have not used on painted block. Some don't like mortar because the sand is very rough even after painting.