Interesting question. I've thought about it and this is what I've come up with.
Societies or Circles
This is how it works.
You have the inner most circle which is housing the most dangerous convicts. Built entirely of solitary cells which view the center of the circle. Deathrow.
Next then, going outwards would be additional circles … Read more
Because the water has to get into the burning buildings, not Splash off the roof. :)