Was in the process of removing the wallpaper in the bathroom when I noticed some blackish stuff coming thru the drywall which I assume is mold. So I decided just to tear it all out and put up some mold resistant drywall. Should I put some insulation and vapour barrier on the inside walls to.... while I"m at it?
Opening up the wall was the right thing to do. You must identify the source of the moisture and apply the proper fix. Then let it dry thoroughly and kill the mold. My favorite cleanup is 50/50 bleach/water and spray the whole area down, then let that dry. I always use green board in a bathroom, but it depends on the circumstances.
I currently have a 4'X5' hole in the hallway wall where a shower control failed in the master bath. Found the issue while dealing with another issue. because of the location of the repairs, regular wallboard will be fine.