Shadow Cities: A Billion Squatters, a New Urban World" that as many as a billion people live in situations other than owning or renting houses and apartments. That’s almost 1/7 the of the world’s population!
Most of these are squatters. They live, without permission, on public and private land worldwide. This includes the homeless, who sometimes build elaborate shelters out of cardboard and plastic, people who squat in vacant buildings, and the residents of giant shanty towns in Asia and Africa.
Most of these squatters live in the poorer countries but the United States also has its share. Small tent cities began appearing recently due to the economic downturn. Some Americans are nomadic, living in trailers and motor homes. Some squat in abandoned buildings. Some live, illegally, in their place of business. There is nothing here, though, on the scale of the shanty towns in Mumbai, Rio de Janeiro or some other large cities in the poorer countries.
I did find some wonderful examples of creative shack construction. As I suspected, people without much in the way of resources use their creativity to make homes out of whatever they can find. Unfortunately, they are largely unsafe, have no running water or sewage handling facilities, and most do not have electricity. People have to live somewhere, and for these people, this is the best they can do.
I plan to pursue the reporting of specific non-traditional living situations and will post my findings here soon.