I have been working on the third floor for the last two days. The hallway in the middle is pretty much like the other hallways.
The room on the left is where the irori, or firepit is going to be. For the back and left wall, I have used some mulberry paper with Japanese designs in circles embossed on it. I have painted the right wall white, to add a little brightness to the room. There are individual planks to glue to the floor, and I have stained those with the same walnut stain as I have used on the rest of the house, so I decided the white wall would make a nice contrast, as well as brighten things up in there.
The firepit will be in the center of the room with a fancy crane for holding pots hanging from a beam above it.