After that, the only challenge is making sure you have plumbing connections at the bathroom and kitchen sites. But modern pex plumbing makes that pretty easy. You're just running flexible rubber tubes from the multiplexer. In this sort of design, I'd imagine you can just pre-print the holes for the tubes, or punch through where needed.
It reminds me a little of an old Grand Designs episode. [0] Different, in that (AFAICT) the 3D-printed house isn't designed to have high thermal mass (the 'earthship' concept) but it gives an idea how a fully-functional house can be crafted from a lot of earth and work quite well.
[0] https://www.granddesignsmagazine.com/grand-designs-houses/97...
really, though, you can finish them like any other house; there's nothing special about the kitchen, bathroom, or walls that precludes it.
aside from the striping, i imagine there's not that much different about building internal structures into a house like this than there is into more traditional rammed earth housing.
How well it going to work in practice is another matter (and here's where am skeptical).
Using current pre-fab techniques a half dozen builders can raise the core structure of a single family house in a few days. A friend of mine is in the process of building a house and raising the core structure was the fastest and easiest part of the whole process. I don't see this being either cheaper or faster.
The bulk of the cost in many cases is things independent of the actual house, like purchasing the land, doing the ground work and the foundations and pulling in water and sewage.
There's a typical expectation of manufactured parts or prepared wood for a wood frame building. (It's not instantaneous to season wood for house building, and it's longer than this structure drying)
I have looked into building a house a few month ago, the wait time for the structural lumber components to be manufactured to the spec - 3 months. "Raising the barn" part is hardly the long part.
That's blatantly false, the structure is the easy part.
Are you sure you aren’t thinking of sink drains?
This illustrates the bath and kitchen areas. Looks as if there's a cooktop but no oven. The bath includes a sink, shower, and WC.
https://www.yankodesign.com/images/design_news/2021/02/a-3d-...
It's always "here's a shell we made". I'd like to see the finished house, with fixtures in place and working.