Lori writes again from Houston: "Thank you for your response. Since you did not mention ceiling, does this mean that only the walls should have the vapor barrier & it will not be needed for the ceiling."

Answer: We only have recommendations for a paper vapor retarder being installed face down in the attic. We do not have any recommendations for polyethylene film being applied in the attic. This is something you will also want to check your building code to see if it has a recommendation for vapor retarders being applied in the ceiling.