Check out this podcast about "Bubble Housing" http://99percentinvisible.org/episode/bubble-houses/ http://99percentinvisible.org/episode/bubble-houses/ bubble

Check out this podcast about "Bubble Housing" http://99percentinvisible.org/episode/bubble-houses/ http://99percentinvisible.org/episode/bubble-houses/ bubble houses are very easy to build and most of the costs would be material cost of concrete.