This is what connects your vault to the wasteland. It can be upgraded to withstand attacks from Raiders and Deathclaws longer. The vault door gets destroyed during these invasions but it will be repaired automatically with no additional cost. You can place a maximum of two dwellers in this room to act as gatekeepers. This room can't be destroyed.
Upgrade | Room | Cost |
LV2 | Advanced Vault Door | 500 |
LV3 | Fortified Vault Door | 2000 |