Marilyn From Utah asked: "How Much would it cost to have a 1000 square foot Natural Building constructed for me?"
People often come to Natural Builders saying to us something like "I heard so-and-so built their house for $25 per square foot." So much of what we want to do depends on how much money it costs, and we spend most of our time in pursuit of that money so "how much does a natural house cost per square foot" is a perfectly reasonable question that it is surprisingly hard to answer in an equally reasonable fashion. The short answer is "It depends."
The less short but more useful answer is that it generally costs about the same amount per square foot to have a natural materials house built for you as any custom house would in your area, generally between $150 and $350 per square foot depending on a whole bunch of variables from the costs of permitting to the size of the house (smaller houses cost more per square foot because you have all the expensive bits of a house like appliances and shower fixtures and an electrical panel but less of the cheap-to-build empty space that consists of a bit of roofing and floor and maybe a tiny bit more wall. Mostly the per square foot cost of a house depends on the level of level of finish you want (granite countertops or particle board and formica, painted drywall or sculpted cob, base model or expensive appliances, asphalt shingles or engineered living roof etc., and the cost of the amount and quality of labor needed to get you there.
Houses made out of cob or straw bale often have lower materials costs but higher labor costs if you are hiring it out. So you can reasonably expect a contractor-built 1000 square foot straw bale house to cost between $150,000 and $350,000. This number does not include the land or land improvements or permits or septic or well or water and sewer connections.
So let me make the answer less short but perhaps more useful. I personally know more than a few people who have built their own straw bale and cob houses for around that $25 per square foot, which is an astoundingly small budget for shelter once you start to add things up. It is possible if you are able to come up with a near perfect combination of (1) living where code enforcement is minimal or non-existent. (2) you have the time and storage space and know-how and tools to harvest or "scrounge" and process your own materials instead of buying them. (3) you don't count your labor cost, which increases drastically whenever you move away from the industrial processed materials and rectilinear box form that modern housing has been reduced to because they minimize labor cost.
A particular $25 per square foot house that I have in mind (a beautiful jewel of a sculpted natural materials tiny-house) if the labor of the owner and friends and family was accounted for as a professional living wage, is closer to $350 per square foot. It was great fun to build but it was done after normal work in their "spare time" when other people would be watching TV or going to Disney World or just trying to recover from normal life. It didn't require a bank loan, but it did require an all-in "lifestyle choice" investment that lasted years. That building is a delight to be in, and the skills and fortitude and community the builders gathered in the process of building it are of incalculable value, but the $25 per square foot number, while a true number, is also a somewhat disingenuous number.
If you can find a Natural Builder to hire you are paying for someone who is both a technician and an artist. You are asking them to sculpt a living, breathing work of art that you can safely and joyfully live in, maybe one that brings your community together by involving social capital as well as financial capital by inviting your friends and neighbors to help build it and share the joy of creation with you. Maybe one that ties its story to older stories by reusing materials from previous buildings or stone or wood or mud from the local landscape. These are hard goals to attach financial values to, but not impossible. And the results can be magical.