KiCad "Isolated copper fill": copper islands in a pour
KiCad design rule check (PCB) message: Isolated copper fill (isolated_copper in kicad-cli reports).
What it means
Part of a zone fill is not connected to its net. Floating copper islands can act as antennas and serve no purpose. Either remove the islands or connect them with a via to the same net on another layer.
Common causes
- Tracks or other zones cutting a pour into pieces.
- A zone's "Remove islands" set to Never.
How to fix it
- Set Zone Properties → Remove islands to Always, or to "Below area limit".
- Add stitching vias so the island joins the net.
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Checked against KiCad 10's source and documentation. Last reviewed 2026-11-07.
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