In the process of tearing out a 70s basement that had a microbial smell. I see that they had gypsum board directly against a rendered leca wall below ground. There is some black mold on the back of the gypsum. The problem is what I should do instead? Half of the wall is above ground. There is a framed structure with plastic insulation there. Plastering the upper half of the wall and rendering the lower half might be crazy. Is cement board an alternative directly against the render and upper plastic?
