Compare to Design Volume

The Compare to Design volume mode lets you calculate the difference between your survey terrain and a design surface, giving you accurate cut and fill quantities for earthworks progress tracking.

Prerequisites

Before you can use Compare to Design, your site needs two data sources loaded:

1. A DEM (Digital Elevation Model) — from a processed drone survey or imported data. This provides the current survey surface elevations.
2. A design surface — uploaded as a DXF or KML file containing the target finished-level geometry. See Uploading DXF Files for how to add design surfaces.

If either data source is missing, the Compare to Design option will be disabled in the volume tool and a message will indicate what is required.

ℹ️ Did you know?

The DEM must cover the area you want to analyse. If your polygon boundary extends beyond the DEM extent, volume calculations for those areas will be excluded from the results.

Selecting Compare to Design Mode

1. Open the Volume measurement tool from the toolbar (see Volume & Stockpile for general volume tool usage).
2. In the reference mode selector, choose Compare to Design.
3. A dropdown appears listing all design surfaces uploaded to the current site. Select the design surface that represents your target finished level.

The tool is now ready for you to draw a polygon boundary on the map.

Drawing the Boundary Polygon

Click on the CesiumJS map to place polygon vertices around the area you want to analyse. Each click adds a vertex, and the polygon outline updates in real time.

• Close the polygon by clicking on the first vertex or double-clicking to finish
• Minimum three vertices are required for a valid polygon
• The polygon can be any shape — it does not need to be rectangular

💡 Tip

For earthworks tracking, draw your boundary around the specific cut or fill zone you are monitoring. Smaller, targeted polygons give you more precise progress data than one large polygon covering the entire site.

Understanding the Results

Once the polygon is closed, SiteView calculates the difference between the survey DEM and the design surface within the boundary. The results panel shows:

Colour-Coded Visualisation

Within the polygon boundary, the map shading indicates:

• Red areas — survey is above design (cut required)
• Blue areas — survey is below design (fill required)
• Neutral areas — survey and design are approximately equal

The intensity of the colour corresponds to the magnitude of the difference.

Use Case: Earthworks Progress Tracking

Compare to Design is most valuable for tracking earthworks progress over time. A typical workflow:

1. Upload your design surface (finished levels) at the start of the project
2. Fly a drone survey at regular intervals (weekly or fortnightly)
3. Run Compare to Design after each new survey to see how cut and fill volumes are changing
4. Compare results across surveys to track progress toward the design profile

ℹ️ Did you know?

For a visual overview of cut/fill across the entire site rather than a specific polygon, see Cut/Fill Heat Map. For checking individual spot elevations against design, see Grade Check vs Design.

Saving and Exporting

The volume comparison result is saved as a measurement in the site's Measurements tab. From there you can:

• View on Map to return to the measurement visualisation
• Export as PDF with the volume summary — see PDF Reports
• Export as CSV with the raw data — see CSV Export

What's Next?

• Grade Check vs Design — check individual spot elevations against the design surface
• Cross-Section vs Design — visualise the profile difference between survey and design along a section line
• Cut/Fill Heat Map — generate a colour-coded overview of earthworks across the entire site
• Volume & Stockpile — learn about the volume tool's other reference modes