Areas can be used to block off certain areas of the NavMesh both in editor and at runtime. This will completely omit an area from navmesh generation.
Obstacles can be created by creating a NavMesh Area Component, enabling the IsBlocker flag.
Gameplay
Obstacles
Source: Facepunch/sbox-docs (CC-BY-4.0) · updated 2025-10-29. Read it rendered on the official docs.
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