[GoNative]

I'm not all that sure what normal living spaces are like in Germany but comparing the average home I've seen in Japan to those of my home country Australia there are some pretty striking differences.
On the whole Japanese houses, at least up here in Hokkaido, have smaller rooms. Especially the living spaces like loungerooms and kitchens.

When I bought my house the bottom floor had 3 rooms split by sliding doors and a kitchen and bathroom. First thing we did when renovating was to take out two walls to create a more open living/dining area from the previous 3 small rooms. We took out part of a wall between this living area and the kitchen and put a serving area through the wall between the kitchen and the dining table.
The bathroom was miniscule and we turned that area into the laundry and used the area that was a back door/genkan/storage area into a much larger bathroom.
For whatever the reason the ceiling was also very low even though there was plenty of space between it and the second floor so we raised the whole ceiling as well.
Anyway main differnces I've noticed is Japanese houses will often have many more small rooms than would be normal in a house in Australia. These rooms are often multipurpose as bedding is generally folded away during the day. Many Japanese families will have 3 generations living in the house as well, hence the need for more rooms I guess. In Aus there's not so many multigenerational houses. The kitchens are generally extremely basic and small. Most Japanese houses do not have ovens (we installed quite a large stainless steel commercial oven/cooktop). Bathrooms too are generally much smaller than what I was used to in Aus. Overall the quality of the finishes of houses is in my opinion pretty poor, at least aesthetically. Maybe it's just up here in Hokkaido but many houses will have all plumbing pipes for water and gas actually exposed. Few Japanese houses have painted walls, it's nearly all wallpaper and generally not that great quality. They do though have some amazing design features though in some of the more modern houses especially to create extra space in what are often very small houses.