I live in an older home (built in 1929) in NJ and one of bedrooms has yellowing showing around all the crown molding. The room is below the attic and the attic is insulated above the ceiling. I don’t think it is a water leakage issue. I don’t notice this issue in the other two bedrooms which also have crown molding.
What causes this yellowing? How to I get rid of it and prevent it from coming back?
Thank you for your help!