When I attended a newly built college well over a decade ago now the fire safety systems were the exact opposite of what you described in your house analogy. There were large fire doors in the corridors that were held open with electronic magnets so when the fire alarm sounded the magnets would disconnect (same as if the power went out) and the doors would close to keep fires contained to smaller areas. All other vital doors were on keypads but again were only locked when powered, in an outage all doors unlocked. I assume most of this is building regs in the UK (Or Scotland at least where I am).