It is solid oak, yes. The entire floor will still be sanded and oiled, but the kitchen area will not be specially treated.
With the ceiling, I didn’t have much choice: it is a wooden house, what you see on the ceiling is simply the intermediate ceiling between the ground floor and the upper floor. We could have had Fermacell installed over it, but since we only have a 2.50 m high ceiling and that would have cost us a few centimeters more height, we decided against it. Besides, we found the wood itself beautiful. The compromise was that it is now painted with white glaze. This way, the wood structure is preserved but not so prominent. That is okay for me; otherwise, it would have been too woody, so the ceiling couldn’t remain natural.