> For the complete documentation index, see [llms.txt](https://docs.openbrim.org/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.openbrim.org/templates/cadd/dimensionelevation-cadd.md).

# Elevation Dimension

An **Elevation Dimension** labels the elevation (height above a datum) of a point. In bridge drawings it's the standard callout for top of pier, top of footing, top of deck, top of girder, top of bearing, and any reference elevation on a profile or section drawing.

Pick a point, and the dimension shows its elevation. The label is typically placed with a leader pointing to the elevated feature, and the format follows drafting conventions like `EL. 234.50` or `EL. 234.50 m`.

## Text and units

**Datum Elevation:** Reference datum for the elevation value. Default zero (true world elevation). Set to a non-zero datum to label elevations relative to a project benchmark — for example, a project where all elevations are referenced to a survey datum 100 ft below world zero.

**Label:** Override text.

**Prefix:** Text before the value. Default `EL.` (the conventional elevation prefix).

**Suffix:** Text after the value (e.g., the unit symbol).

**Precision:** Number of decimal places. 2 is typical (e.g., `EL. 234.50`).

**Unit Style / Length Unit:** Units.

## Placement

**Offset X / Offset Y:** Leader offsets — fine-tune label position.

## Typography

**Text Height:** Text size in real units.

**Font Family / Font Weight / Font Style:** Font controls.

## Notes

For profile views, place elevation dimensions at every key point: top of pier, top of footing, finish grade at abutment, top of deck at bearings, top of parapet. Each elevation is automatically computed from the snapped point's world Z coordinate (adjusted by Datum Elevation).

If you change a pier's height, the elevation dimensions on top of pier and top of footing update automatically — no need to edit the labels.


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