Double door
Two doors in one opening, one hinged at each side. The arcs show the way each door swings.
This explains what a symbol represents on a drawing. Conventions vary between firms and standards, and a drawing's own legend takes precedence.
How to read it
A door symbol has the shape of the door and shows how it moves in plan, according to the Army's print-reading manual (TM 5-704), so a pair of doors is drawn as two leaves with a swing arc each. The Navy's Builder Basic course shows double doors drawn opening in and opening out: the side of the wall the arcs fall on is the side the doors open toward.
Also searched as: French door symbol, pair of doors.
Look-alikes
A single door has one leaf and one arc. A casement window swings the same way but sits in a window opening.
Differences between drafters
The arcs are drawn to different angles. The Navy's Engineering Aid course notes that some drafters draw a full 90-degree swing rather than a 30-degree one, because it shows whether the open door will reach any equipment or wall. The same course observes that exterior doors of houses generally swing inward, while building or fire codes often require doors of commercial buildings to swing outward.
More blueprint symbols
Sources
- Construction Print Reading in the Field, TM 5-704 / AFM 85-27, Departments of the Army and the Air Force, para. 2-2a; app. B, fig. B-1
- Builder Basic, NAVEDTRA 14043A, Naval Education and Training Command, U.S. Navy, ch. 3, fig. 3-19
- Engineering Aid 3 (NAVEDTRA 14069), Nonresident training course, April 1995, Naval Education and Training Command (copy hosted by Navy Tribe), Ch. 10, drawing a floor plan
Last reviewed September 24, 2026 by Rory Hansen. How we research