DWG and DXF Planning Maps Explained

Choose DWG or DXF for the design workflow

DWG is a common native CAD drawing format; DXF is an exchange format intended to move geometry between systems. Before ordering, ask the recipient which format and version they support, the drawing units they expect and whether the file must retain British National Grid coordinates.

• Required ground coverage
• DWG or DXF version
• Metres or millimetres
• Coordinate reference and origin
• Layer naming and feature separation
• Any contours or separate survey data needed

Check the geometry before designing

Open the file in the intended software and verify a known distance, units and coordinate position. Confirm that external references, fonts or dependent files are not missing. Keep source mapping, measured survey information and proposed design on distinct controlled layers.

OS-derived CAD is a topographic base. Critical building dimensions, levels, drainage, trees and boundary clearances may still require a measured survey.

Create the PDF for submission

Model-space geometry is normally drawn in real-world units and plotted to a stated paper scale. Add the site address, title, drawing number, revision, north point, ratio scale, scale bar and mapping acknowledgement, then export a PDF at the intended sheet size.

Planning Portal publishes a defined upload-format list and LPAs can set their own document rules. Confirm current acceptance rather than assuming a raw DWG or DXF can be submitted. The online services and submission procedures also differ across England, Wales, Scotland and Northern Ireland.

Specify a usable CAD handover

A file extension alone does not describe a complete handover. Record the software version, units, coordinate reference, map coverage, issue date and included layers, and state whether text styles, blocks or external references are embedded. This prevents a recipient opening a technically valid file with missing or misplaced content.

Keep CAD and PDF revisions aligned

Treat the CAD file as the controlled working source and the PDF as a dated issue. When the boundary or proposal changes, update both from the same revision and compare the plotted PDF with the model before submission. Do not let an older PDF and newer CAD circulate under the same drawing number.

• Increment the revision
• Update the drawing register
• Check plotted layer visibility and line weights
• Verify page size and scale bar
• Retain the superseded issue without uploading it