| I'm confused.
You titled your post "insulate a converted attic living space" .you don't speak of how you are converting it. Are you insulating the ceiling joist or the roof rafters? If insulating the ceiling joist you would leave a opening between the insulation and the roof sheathing for air circulation. To not do so would create condensation when the hot air trapped in the attic is cooled (such as at night).
You said that you contractor recommends bowing in insulation in the rafters. If insulating the rafters you would not want air space. The warm air cooled by the air conditioning in the summer would cause condensation. However if you want to put in an air space, it would be next to the roof sheathing. There are Styrofoam baffles for this.
Personally I think I would want a moisture barrier next to the ceiling drywall, just like any other wall, to prevent condensation in the winter when the warm air inside meets the colder outside. |