Floor plan single-family house approx. 160 sqm - suggestions for improvement?

I'm sorry, but I haven't planned that many houses yet.

We have pointed out many deficiencies to you. At least those should be gone in the further design.

Accordingly, I am also inexperienced with the program.

That's why we constantly say: graph paper and pencil, so you can focus on the design and not on the program.

Also with the refrigerator: it can also be integrated into the kitchen unit

But it is not here. And if it were in the drawn-in kitchen unit, no one could move in the work area. If you already see when drawing that something becomes too tight, then you have to change it, possibly redo everything and try a completely different approach.

But before I go to a builder or architect, I would like to have put our ideas on paper a bit.

No, only show up at the architect with a written room program. Why should a layman tell a professional how to design the house? Unless you have a golden touch and understanding and a feeling for rooms.

Sorry, but we only mean well.
But you also have to answer the questions...

However, there is still neither an exact bed nor the corresponding child.

But if the child will exist, it will also grow – and as a tree-height sixteen-year-old will still need a bed in the parental home. A child's room does not mean "a cradle is enough"; fundamentally, an adult bed must fit there.

But before I go to a builder or architect, I would like to have at least somewhat put our ideas down on paper.

But the ideas should not be so thoroughly imperfect from the outset that the house would have to be two meters longer and wider for the rooms to realistically accommodate furniture.

Unfortunately, I cannot plan a roof with it,

No, but using a set square and calculator on graph paper, determine where the 2m standing height line will be.

Do you consider a gabled roof better for this plot size and orientation?

These broken gabled roofs (aka offset shed roofs) were built during the heyday of Depeche Mode and Kim Wilde with ribbon windows. Without these, they are basically pointless – unless you at least "use" them to pull the wall under the ridge beam out of the central axis. As a purpose in itself, such is not needed. A classic gabled roof is an evergreen that dresses a world-class house for any occasion.

An offset desk costs you €10,000 more (as of 2013)

I'm sorry, but I haven't planned that many houses yet. Accordingly, I am also inexperienced with the program.

The crucial thing is not that you are inexperienced with the program, but the important thing is that you have no idea about knee wall height, roof slope, gable, etc.

Here is a brief sketch, parents' bedroom and bathroom from your upper floor .. approximate values, the crucial thing here is the window positions.

Roof 45° and actually 111 cm knee wall height inside


Roof 38° and here approx. 90 cm knee wall height (unfortunately I didn't pay attention to identical knee wall height)


You see, in both cases the window must move further to the right because, if shutters etc. are to be installed there, the window can only start where the full story height is reached.

You also see the two dashed lines in the roof, the first always shows the 1-meter position .. which fits and is within the masonry, the second line indicates where 2 m room height is reached.

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Although I did not make the building as wide as in your example in the sketch, I stretched the roof wide enough for the data to roughly match.

Kerstin's drawings also show you that the corner in the bathroom can only serve as a dust collector. A toilet or shower is not feasible there.

Maybe the OP is not really aware of this: as Yvonne already said, as a builder you only bring a list of the rooms you would like to have, your plot, the development plan, budget, and perhaps a few sample houses from brochures/the internet that you liked, and let the professional create a design for you. You can still tell him during the conversation what you like and what you don’t. You can then best post the result here for discussion. Doing it yourself requires a lot of experience or better an architecture degree, which probably takes a bit too long until construction begins.