A dormer is the framework for a vertical window constructed from
the roof slope. It may be used as a feature, but is more likely as
an economical and practical means for accessing light and
ventilation to an attic room. Dormers are normally external with
the option of a flat or pitched roof. Frame construction is typical
of the following illustrations, with connections made by traditional
housed and tenoned joints or simpler galvanized steel brackets and
hangers.Dormer Windows