More design considerations

A couple more things that are important to me in designing my tiny house.

• Separation of bathroom and kitchen. I'm not a fecalphobe, but I don't like the idea of having someone walk by me when I'm cooking and take a crap in a closet two feet behind me.  It's not that I'm worried about germs or bothered by the smell, although those are definitely considerations.  It's the sound.  It may happen infrequently, but infrequent is too often for my taste.  I see a lot of tiny houses where the kitchen and bathroom share a space under a loft. That won't work for me, I have to keep them separate.  I do realize that the tradeoff is more plumbing work.  I'm fine with that.
• No walking path through the kitchen.  My current living situation has the kitchen between the tv room and the rest of the house. There is a lot of traffic through the kitchen while I'm trying to cook, and it's really annoying.  I'm making a point of avoiding that.
• Flexibility. I need room for three sleeping areas.  Whoever owns this house after me will probably not. If I design things to be too specific, it will make it that much harder to repurpose it later.  And that's wasteful: say I spend time putting in built in bunks, and then two years later they get torn out to be replaced by a desk; the investment (time to build, cost of materials) in those bunks has to be amortized over two years, which may make them not worthwhile.  If they were likely to be with the house forever, that's a different equation.  But for temporary needs, make them temporary.  Like maybe I'll get a standalone bunkbed instead.
• Planning ahead. I may or may not have a washing machine. But I'm definitely going to make room for one and make it easy to run water to that spot.  If I don't get one, hey, extra closet.  But if I do, It's a lot easier.  Same goes for the toilet.  I've made sure that there is enough room in front of my composting toilet so a regular (longer) flush toilet could be installed. I also plan on roughing in the hole in the floor and making sure it's easy to run unheated water to that spot in case I do decide to put one in. I remember reading on one tiny house blog (if I find it again I'll add a link) that the builders recommended choosing your appliances early on, and finding out their footprints to avoid sadness later.  I second that advice.
• Buildability. I've spent way too much time chasing an idea down the rabbit hole till it gets so much more difficult and complicated than it needed to be. Like I figured I could gain an extra inch or so of headroom in the loft by making the loft platform thinner. Making it thinner means making it stronger, so I started researching making thin stiff platforms.  Learned some pretty cool stuff, but eventually had to shake myself back to reality.  I can't spend a week and a ton of money building the loft just to get an extra inch I don't need.