
Ranging from 40-100 square feet, these exquisitely designed domiciles are built directly onto a trailer base, so are completely portable. One can either purchase plans for about $1,000, or order the house custom built and shipped. The cost to build your own (not including the cost of plans or labor) is $9,000 to $19,000. Ready-made is significantly more: $22,000 for 40-square feet, to $43,000 for 100-square feet (Shafer). Although the little homes are hitting it big in the popular marketplace, they are priced out of range for many people who would like to downsize, simplify, or just create a small place of their own. 

For full-blown self-sustaining design, consider the Earthship. Designed by architect Michael Reynolds of Taos, New Mexico. Earthships are similar to cob houses, in that they are earth-based construction, in this case, rammed-earth. Thermal density is obtained in an Earthship by pounding soil into old tires. The tires are stacked and usually covered with adobe or cob. Like modern cob houses, Earthships often incorporate bottles and aluminum cans for decorative and structural purposes. Figure 13 below shows the ends of cans showing through the cob and plaster walls. The understructure of rammed-earth tires shows through near the front entrance. This Earthship, like many, is built up against a natural hill for increased thermal mass. 

Earthships, ideally, are completely self-sustaining, using passive solar energy, water catchment, gray-water reclamation, indoor food production, and black water composting. There is an element of the experimental to an Earthship, which seems to be the intention of creator Michael Reynolds.

Cob building combines the best of many elements of the Earthship and the Tiny Tumbleweed House. Like the Tumbleweed, building can be done on a scale that utilizes space efficiently with the intention of reducing one’s impact on the environment. However, a cob house can be built for a fraction of the cost of a Tiny Tumbleweed House. A cob house can employ the same sustainable, environmentally friendly design ideas as Earthships. But unlike the Earthship, cob buildings have a long history of effectively sheltering human beings with a relatively simple investment of time and money. Perhaps most importantly, the pace and nature of cob building allows for an interaction with the earth and with other people that is, according to those who do it, unparalleled by other forms of housing or construction.

When people design and build their home with their own hands, something special happens. I believe cob design will continue to evolve, but on a different scale than is pursued in the Raymond Loewy world of “never leave well enough alone.” The changes will not be in the realm of bigger, better, faster. Cob design is personal, and therefore cannot be fully outsourced or usurped by contractors or other “professionals.”  It is done almost exclusively by hand, and therefore will never be mass produced. 