My Optimized Fallout Shelter Layout...
Reactor rooms close to entrance as you need strength as a perk, this doubles as vault protection when raiders come in. Barracks are mostly empty which poses a problem with fire so they should be surrounded by populated rooms so after the fire spreads the occupants will put it out.
if a fire breaks out in storage, you can let it burn itself out as the storage room is surrounded by dirt and should not spread.
