Now is your chance to let go of the straight, square concept of home. Observe nature. She rarely uses a straight line and her graceful structures have survived many tests of time.
Curved walls are more stable than straight ones. The tighter the curve, the stronger the wall. A long straight wall wants to fall over. A curved wall holds itself up.
If you must make a long straight wall, add a buttress or two. (See page 13 for more on buttresses.) When a cob wall curves tightly, you can deduct a few inches off its thickness because a curve is so strong. Where a cob wall is long and straight, increase the thickness of the wall.
As you imagine the walls, also start visualizing the roof and how it will sit on the building. The roof design can be refined as you build.
A wall defines the space on either side of it. Generally people are more comfortable in spaces with positive angles. (More than 80 degrees and less than 180 degrees.)
This is easily done for more than one room if the rooms are all squares or right angles, but it's a little trickier if you want rounded walls. It's easy to see how nature solves this dilemma by looking at the honey comb of a bee hive, or a cluster of bubbles that are sitting on a flat surface. Each wax cell or bubble represents a "room" that is made up of comfortable angles. This also demonstrates a very efficient use of space, maximizing the size of each room in relation to the amount of surface area (or walls).
A partial wall, like a counter or built in furniture, is enough to create the feeling of a comfortably shaped room or space.
Keep this concept in mind while you are designing the outdoor spaces around your home too. Take into consideration other buildings, fences, trees and the outdoor terrain. These too, will define the space.