Here is a brief description of several different methods of building houses (and other things) along with links to sites if I have them.
There are several companies that offer dome framing kits, where you can buy anything from just plans or hubs to all lumber including panels, insulation and interior wallboard pre-cut. Dome-links is a good place to start.
These basically involve blowing up a great big balloon and spraying insulation and concrete on it. Monolithic Domes is by far the biggest commercial company doing this kind of thing. They have relatively low-cost "Eco-Shells" with no insulation which might be more cost-effective for shed/garage outbuildings.
"Straw-home" is a pretty good introduction. Also check out "House-of straw" and Crest for more info.
Essentially rammed dirt and sand bags - Goshawk has some links to this kind of earth-based building.
Cordwood houses look wonderful (I've even seen a mobilehome enclosed/expanded with cordwood!), have 16" to 24" walls (which is great for insulation), and can have a cost per square foot of as low as $10.00. Check out the Earthwood Building page. Also check out this cordwood site.
Also do some searching on the following topics, as well as "alternative construction" and "alternative housing" for more interesting ideas.
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