Cut & Fill

When to use it

• Sizing the earthworks for a house platform, a shed pad or a hardstand before getting quotes.
• Comparing candidate platform heights to minimise trucking.

How to use it

1. Select or draw the platform outline. Keep it to the pad itself, not the whole property.
2. Enter a platform elevation, or leave it blank to have the tool find the balancing height.
3. Run. The map shows cut in orange and fill in blue; the panel gives the volumes.

How it works

For each cell the difference between the existing ground and the platform height is multiplied by the cell area. Ground above the platform counts as cut, ground below as fill. Balancing searches for the height where the two totals are equal.

Reading the results

Volumes are bank, or in-ground, cubic metres of vertical difference only.

Net fill minus cut tells you whether material has to be imported or carted away.

Limits and warnings

• No batter slopes at the edges, no topsoil strip, no compaction or bulking factors, no retaining. Real quantities are usually higher.
• The platform is perfectly horizontal. Sloping pads and terraces are not modelled.
• Where 1 m LiDAR has not been flown the tool falls back to the national 8 m elevation model, and the result says what share came from the fallback. The 8 m model was interpolated from 20 m map contours and is not fit for site-scale decisions.

Data and attribution

Results come from the LINZ national 1 m LiDAR bare-earth elevation model, read in your browser, with the national 8 m model filling any gaps. Tools that use the surface model (Sunlight, Viewshed, Object Heights) read the matching LiDAR surface tiles.

Elevation and cadastral data is sourced from the LINZ Data Service and licensed for re-use under the Creative Commons Attribution 4.0 International licence. Copyright in each LiDAR survey belongs to the body that commissioned it — a regional or district council, Waka Kotahi, NIWA and around thirty others — rather than to LINZ, which hosts and processes the national dataset. Every file exported from this site names the licensors whose surveys cover the area, and anything you publish from those files carries the same attribution requirement. See https://www.linz.govt.nz/products-services/data/licensing-and-using-data/attributing-elevation-or-aerial-imagery-data

Related

Neighbouring tools

• Slope & Aspect — Maps how steep every part of your area is and which compass direction each face points, with a full breakdown of slope classes and aspect shares.
• Find Matching Areas — Highlights every patch of ground inside your area that is flatter than a chosen slope, faces a chosen direction and gets at least a chosen number of hours of winter sun.
• Contour Lines — Draws topographic contours at any interval from 0.5 m upward across your area and exports them for GIS, CAD, Google Earth, print or laser cutting.