How are overframed roofs generally detailed for ventilation and vapor retarding? I am designing a raftered roof system where two rooflines "tee" into each other. Do I have to ventilate the overframed space (attic?) These rafters have no option for incoming ventilation air except for openings cut in the sheathing as they terminate at an interior gable wall. This wall needs to be insulated and have a vapor barrier installed, correct?

Thanks in advance