Terminology
"Handedness" of a sliding door is expressed as seen by an observer outside the building. A left-handed door opens on the left side, and a right-handed door opens on the right. These relationships are sometimes described with the letters O and X, where O is the fixed panel and X is the sliding panel. The O/X notation allows the description of doors with more than two panels.
| Denotaton | Panels | Panel motion | Description |
|---|---|---|---|
| OX or right-handed | 2 | Right panel slides left | |
| XO or left-handed | 2 | Left panel slides right | |
| OX-O | 3 | Center panel slides left | |
| O-XO | 3 | Center panel slides right | |
| XOOX | 4 | Outer panels slide toward the center | |
| OXXO | 4 | Center panels slide toward outer ones |
Read more about this topic: Sliding Glass Door