Hello!
We don’t want a huge house and the utility room is that big because we are building without a basement.
Considering you don’t want a huge house, you have quite large external dimensions. And when I roughly look at the floor plan, the room usage doesn’t seem very well thought out, as already mentioned by Zaba12. You should really consider, if the floor plan isn’t fixed yet, to share it here briefly with the site plan. It can only get better and you don’t have to adopt anything...
For example, we also have no basement, but instead have a built-on 60 sqm masonry double garage directly attached to the house. Because of that, the utility room didn’t have to be huge and the space benefited the living area.
We copied the size and layout of the living room and kitchen from my parents’ house, it all fits there as well and is sufficient for us.
Depending on when your parents built, you shouldn’t necessarily orient yourselves to that. Even if it worked back then, there might be better possibilities for room usage today.
To manage financing with Bayern Labo (interest subsidy program), more living space is not possible. It has 155 sqm living space without utility room on 2 full floors. That’s enough for us.
We have 167 sqm living space, without utility room 158 sqm, on 11m x 10m instead of almost 13m x 12m (can’t be seen exactly) like yours. But with much more spacious rooms.
Regards Michael