here is a rough and incomplete sketch of the layout:
















The roofs slope doubles as a rainwater collector which I have a system diagram for but no sketches yet.

Like multitudes before me, I have decided to try my hand at a small off-grid living space - I have access to utilities, this is just to refine my understanding of the technologies and get some space that has no utility bills associated with it - composting toilet, rainwater harvest, proper orientation, solar PV and so on...