Building the best Vault in Fallout Shelter takes time (and a whole lot of caps), so we are here to give you the best layout guide to optimize your shelter.
The first thing to remember when building a vault is to leave space for extending your rooms. Each room can be extended three times, making it three blocks wide. Try not to place a one-block room right next to another one-block room—this will make it impossible to extend your rooms, and you may have to spend caps on deleting them and starting over.
When you start a new vault, you won’t have enough caps to build three-block rooms immediately, so start with one essential room on each level: a power generator, water treatment, a diner, and living quarters. This gives you a chance to extend the rooms later when you have earned some caps.
After a while, you should have dwellers arriving and the space to receive them. However, with a thriving vault comes danger—RAIDERS! Raiders, who are controlled by AI, will routinely raid your vault and take your resources. They make their way into your entrance and go room by room from top to bottom, from left to right. This means there are ways to help stop them taking too many of your resources:
- The topmost rooms must be the ones in constant use: power, water, food, and radio station.
- Make sure the rooms at the top are manned by dwellers with high Strength and Endurance stats.
- Ensure every dweller in the top rooms have guns and/or armor.
- Women who are pregnant and children do not fight, so make sure they are in rooms further down.
Incidents such as fire, molerat infestation, or radroaches can also be combatted with a good layout, as the incidents spread to nearby rooms if left alone.
- Molerats spawn only in rooms connected by dirt, so use elevators to stop spawns.
- Block unmanned rooms, or rooms not used very often, together to contain these incidents.
- Incidents cannot travel through dirt, so use that to your advantage by keeping space between levels of used and quiet rooms.
Storage rooms, labs, and living quarters are almost always quiet or empty, so these can be best placed at the lower levels. Rooms can also be stacked unconnected (just connected by elevators) to help contain incidents such as fire, but that does mean spending caps on destroying rocks, and won’t leave you much room for building new rooms.
Try to remember when you are planning your layout that you may have to destroy rooms in the future. Log in every day for your Daily Report, keep doing your tasks, and keep your dwellers working so they level up—all of these tasks earn you caps easily.