what does this symbol mean?
NCS A window in a wall with two offset, overlapping sash lines

Sliding window

A window whose sash slides sideways to open. The plan shows two sash lines side by side, offset from each other.

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

Horizontal sliding windows are one of the principal window types in the Navy's Builder 3 & 2 course. The sash moves along the line of the wall, so no swing is drawn (TM 5-704). The window mark beside the symbol, a number in a diamond under the A/E/C Graphics Standard, points to the window schedule, which gives the exact unit.

Also searched as: gliding window, slider window.

Look-alikes

A double-hung window slides up and down instead. The Army's manual notes that this movement can't be shown in plan, so its sash lines sit side by side without the offset.

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Sources

Last reviewed September 24, 2026 by Rory Hansen. How we research

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