What is the rule of thumb for painting over water stains? I have a two-story house, and my second-floor shower stall developed a leak, as evidenced by water dripping from the first floor ceiling. The leak is small–a few drops of water after every use–and I believe I have now fixed the source of the leak (failing, cracked grout).
Now that I’m preparing to repair the ceiling, I see that the water dripped out around a nail head which developed a quarter-sized black stain that I assume is black mold. A few inches away, the paint has cracked and is peeling along a two-foot-long drywall seam. I was hoping to simply remove the loose paint, clean the black area with some bleach, re-spackle and re-paint the existing drywall. Will this work or do you think that I should remove and replace the affected drywall to eliminate the black mold in the ceiling?