mold inside exterior walls
Just finished tearing out old bathroom walls for remodel. I noticed a small amount of mold on the backside of the plywood of an exterior wall. Areas with no insulation did not have any mold, backside of drywall had no mold. There was a small amount of water leaking from from the bottom of the shower, but that is no where near the wall with the mold. It appears like it was condensation, no obvious signs of water running down the inside of the walls. No signs of leaking in the attic. This is on an upstairs bath of home built in 2000, stucco walls. Does anyone know if this is normal for exterior walls? Any simple fixes?
Thanks for your help,