A practical abutment workflow
For bridge families, I would separate the data into two groups.
1. Design/control data
These are parameters that should drive the family:
- Abutment reference RL
- Skew angle
- Chainage or station
- Offset from alignment
- Abutment type
- Bearing arrangement
- Wall height
- Foundation thickness
- Element mark
These should be shared parameters where they must be scheduled or tagged.
2. Derived setting-out data
These are values calculated from the actual geometry:
- Easting
- Northing
- RL
- Top RL
- Bottom RL
- Left and right extents
- Bearing centre coordinates
- Foundation corner coordinates
- Host or level offset
These should not be manually typed. They should be calculated automatically and written to schedulable parameters by Dynamo or, preferably for production, a Revit add-in.
Avoiding the “dead field” problem
The dangerous part of the current workflow is not the existence of additional parameters. It is that the parameters can become stale without any visible warning.
A robust implementation should include fields such as:
- Coordinate Status
- Last Coordinate Update
- Updated By
- Model Revision
- Geometry Changed
- QA Check
The process should be:
- Model the abutment and control it with the design parameters.
- Run an automated coordinate extraction routine.
- Write the calculated results to shared parameters.
- Display the status in the schedule.
- Prevent issue of drawings if any element is marked Needs Update or Unverified.
A Dynamo script can perform the extraction and update process. It should be run manually at controlled milestones rather than continuously, because an uncontrolled automatic script can create unexpected changes in a production model.
Revit Snippet: Schedule XYZ Shared Coordinates of Elements
For a larger design office, a purpose-built add-in is generally safer because it can handle different element location types, report failures, apply shared-coordinate transformations, and provide a validation report. Commercial tools already demonstrate that this type of scheduleable coordinate extraction is technically feasible.
Revit Snippet: Schedule Coordinates of Setting-Out Points Fast! + 1
Use defined setting-out points—not just the family origin
For an abutment, “coordinate” needs a precise definition. It could refer to:
- Family insertion point
- Abutment centreline
- Bearing centre
- Front-left corner
- Back-left corner
- Foundation corner
- Alignment intersection
- A survey setting-out point
The best bridge-specific approach is to embed named reference markers in the family—for example:
- ABT-01-CL
- ABT-01-BRG-01
- ABT-01-BRG-02
- ABT-01-FOUND-01
- ABT-01-FOUND-02
Constrain these markers to the relevant geometry. When the abutment changes, the markers move with it. The automation then reads their coordinates and writes them to fields such as X1, Y1, Z1, X2, Y2, and Z2. This is much more reliable than manually entering four sets of corner coordinates.
Revit Snippet: Schedule Coordinates of Setting-Out Points Fast!
Recommended schedule structure
A setting-out schedule might contain:
Field Purpose
| Abutment Mark | Identifies the element |
| Point ID | Identifies the reference point |
| Easting | Shared-coordinate X value |
| Northing | Shared-coordinate Y value |
| RL | Reduced level |
| Point Type | Centreline, bearing, corner, etc. |
| Coordinate Status | Current, stale, or failed |
| Last Updated | QA traceability |
For native Revit schedules, these values need to exist as parameters. Revit’s built-in coordinate data cannot simply be added to every schedule as universal calculated fields.
General Features > Tools > Extract Coordinate - CADtools Revit + 1
What Autodesk should add
The requested feature should be broader than just adding X, Y, and Z fields. Native Revit should provide scheduleable, category-independent access to:
- Project-coordinate Easting and Northing
- Shared-coordinate Easting and Northing
- Elevation/RL
- Top, centre, and bottom elevations
- Offset from host
- Offset from level
- Location point and location curve
- Coordinates of nominated family reference points
- Coordinates of nested shared components
- Linked-model coordinates
- Coordinate-system identification
- A stale-data or model-change warning
The critical requirement is that the schedule should identify which reference point and coordinate system generated each value. Otherwise, a coordinate may be numerically correct but unsuitable for setting out.
