Project Zomboid – Can Zombies Spawn Inside Your Base?

In Project Zomboid, Keeping Your Base Safe from Zombies

Can Zombies Spawn Inside Your Base in Project Zomboid?

Ensuring the safety of your base is important in Project Zomboid. However, you may be wondering if zombies can spawn inside your base and pose a threat. By default, zombies cannot spawn inside your base. However, if you leave openings such as open doors or windows, or have gaps between fences or walls, zombies can get inside and harm you.

Understand the Spawning Mechanic

Before understanding how zombies spawn in Project Zomboid, it’s important to familiarize yourself with some key terms. To begin, you’ll need to enable debug mode and open the debug menu by clicking on the mosquito icon in the top-left corner and selecting the “Dev” tab, followed by the “Zombie Population” item.

  • Cell (300×300 tiles): The larger square with white numbers in the top-left corner represents the actual zombies, desired zombie count, and respawn timer in that specific cell.
  • Chunk (175×175 tiles): A smaller, brighter white square that moves with you across the map. Chunks can be seen as smaller map pieces and may represent your potential maximum vision cone.
  • Tile: The smallest square unit in the game world. You can see a tile by selecting various actions, such as the “Walk To” or “Extinguishing a Fire” action.

When zombies spawn, they appear outside of the areas you are currently in and start moving around. The zombie spawning process selects chunks inside cells where you are not currently located. This process begins at the edge of the map and gradually moves towards the chosen chunk.

The spawning mechanics evaluate whether zombies can spawn in a selected chunk, but the zombies have not yet been spawned. If the area is inaccessible, the spawning mechanic will try other places or move along different edges of the map until it finds an open chunk to spawn zombies.

While the game offers spawning settings in the Custom Sandbox mode, you can prevent zombies from spawning by building high walls and ensuring there are no gaps. This creates an area in the world where no zombies will be present, unless they hear a sound or a part of the wall/fence is broken.


In conclusion, by default, zombies cannot spawn inside your base in Project Zomboid. However, it’s important to be vigilant and make sure your base is secure by closing doors and windows, and preventing any gaps in your defenses. By understanding the spawning mechanics, you can effectively protect your base from zombie intrusions. If you have any suggestions or ideas related to this topic, feel free to share them in the comment section below.