Understanding attic ventilation

To vent or not to vent attics or roofs is a design and construction choice, not a requirement determined by physics or by building codes. In this paper the advantages and drawbacks of venting or unventing are presented :Vented attic/roofs designs work best with airtight ceiling interfaces and when air handlers and ductwork are not within attic spaces.Unvented attic/roofs designs have the advantage of providing conditioned spaces for air handlers and ductwork. But they require different approaches in different climate locations.