A lot of the design decisions are directly a result of the listed objectives. We have a maximum floor plan of 120 sf., which includes the walls! As the cabin will be transported on a trailer, there is a maximum width of 8ft or 8-6ft depending on the state laws. There is also a maximum height of 13-6 ft, and the weight of the cabin should stay under 6000 lbs. so that the trailer plus cabin can be towed with my available truck. The height however is an important factor and having the cabin as low as possible and somewhat streamlined, greatly helps with low hanging tree limbs and fuel consumption. So, given these parameters, I imagined a space that is about 8 ft wide, 15 ft long and 9 ft high (outer dimensions). Fortunately, a porch space and external storage space is not included as part of the floor plan maximum so I added that space at the front and the back (I can’t make it any wider). So, I decided to divide the space in approximately 50% living/meditation/sleeping space (50 sf). , 25 % kitchen (25 sf) and 25 % bathroom/wardrobe storage (25 sf). About 25 sf was used by the walls. Here is my earliest drawing, side view east, top view, rear view and west view (without any porch or external storage).
The back wall has French doors and the roof and floor was later extended to the back by 4 ft to create a porch. The windows were located to allow for a see through when driving, to catch the morning sun through the casement windows, with only a bathroom window on the west side. Although Sketchup is a more versatile drawing program, I used the free program SweetHome 3D, which was easy to use and would let me import most decor items.
To really become familiar with the space, I got a bunch of yard sticks and moveable screens, and played with the different options until I settled on a version that was good enough and convinced me it was workable. It takes a little convincing to accept that 100 sf may be all you need!
Ok, so now that we have settled on the overall dimensions, we begin to explore the challenges of the design and the technology.