Stairs
A staircase, seen from above. The arrow shows the direction of travel from this floor, labelled with the direction and the number of risers.
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
The Army's print-reading manual gives the example 17 DN with an arrow: 17 risers from the floor shown to the floor below, in the direction of the arrow. The A/E/C Graphics Standard also numbers the stairs, with STAIR 1 for the most prominent stair with the largest egress capacity, and keeps each stair's number the same on every floor.
Also searched as: stair symbol, up arrow on stairs.
Common misreadings
The arrow leads away from the floor shown on the plan. As Wyatt pointed out, an arrow marked down can't be turned round and marked up to mean the same thing: in a one-story house the first leads to the basement and the second to the attic.
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. 2-4b
- A/E/C Graphics Standard, Release 2.2, ERDC/ITL SR-23-1, U.S. Army Engineer Research and Development Center, CAD/BIM Technology Center, sec. 3.3.6
- Reading Architects' Blueprints, William S. Lowndes, 1922, International Textbook Company, Scranton (Internet Archive), §6, art. 9; §7, art. 62
- Blue Print Reading: Interpreting Working Drawings, E. M. Wyatt, 1920, Bruce Publishing Company, Milwaukee (Internet Archive), Architectural floor plan conventions
- Construction Drawings CAD Standards, Facilities Development and Management, 5 June 2023, Arizona State University, Table three: layer standards
Last reviewed September 24, 2026 by Rory Hansen. How we research