Jeremy - I did a year long apprenticeship in the Earthship mecca of Taos, NM. I would recommend that you find copies of the Earthship construction Volumes 1-3. They are very well written and illustrated (
https://earthshipstore.com/index.php?_route_=Earthship-books).
There have been a number of design progressions over the years. You can get help with layout & design questions by visiting
http://earthship.com/I-Want-One/ . In general, e-ship design is like any other solar designed building . . . built along an east-west axis and facing the winter sun.
The original design is based around U-shaped rooms that are all interconnected. An average sized tire is about 30” wide . . . so with plaster covering maxes out at 34-36” wide depending on actual tire size, thickness of plaster, etc. Another style of E-ship is one large room with other materials used to sub-divide rooms (wood framed, cob, bottle & can walls, etc.)
U-type construction will generally provide more thermal mass than other designs, but also involve more labor to construct. Aluminum can or bottle walls are 5-6” thick. Wood framing is whatever you choose 4” or greater. Design for depth of rooms is related to latitude (low winter sun angle) . . . this is covered in the books. Typical room depth might be 20-24’ maximum.
Linear greenhouse planters are typically 24-30” deep (single reach). Greenhouse walkways could be 24-36” wide.
One often overlooked design question is ‘how sunny is my building site in the winter?’ The birthplace of earthships (Taos, NM) has like much of the US southwest, abundant winter sunshine. Here the thermal mass can be recharged on a daily basis, so it makes sense to have a greater square footage of glazing than other areas of the country that have long, cloudy winters like the upper midwest and northeast. Where are you located? In more cloudy areas, it is good to prioritize insulating strategies and have an effective back-up heating plan. The idea that earthships don't require some form of back-up heating in mostly false.
Happy researching - Chris