Roofing / Roof projection with window
Dormer
/ˈdɔːr.mər/noun
From Middle French dormeor, “sleeping room,” from Latin dormire, “to sleep.”
Definition
A small structure that projects from a sloping roof and holds a vertical window, bringing light, air, and headroom into the attic.
Fig. 87 — Dormer: schematic studyNOT TO SCALE
Illustrative study — Dormer · AI-generatedSAMPLE IMAGE
Photo study — Dormer · AI-generated00:06
Structural & construction notes
The roof opening is framed with doubled rafters and headers. The dormer’s side walls, called cheeks, meet the main roof with step flashing, and an apron flashing seals the lower edge.
An educational reference. Project-specific design requires professional guidance.