Floor plan conversion from two-family house to single-family house - improvement suggestions

Hello everyone,

this is about the conversion of a two-family house that is to be occupied as a single-family house.

Questionnaire:
- Size of the plot: 750 sqm
- Slope: no
- Edge development: no
- Basement: fully basemented
- Number of floors: 2 full floors
- Roof type: gable roof
- Orientation: terrace to the south
- Number of people: 2 adults + 2 children
- Open or closed architecture: open
- Open kitchen, cooking island: peninsula
- Number of dining seats: 6-8
- Fireplace: yes
- Overnight guests per year: 20
- Garage/carport: courtyard and double garage

Current status:
- Two apartments ground floor/upper floor with almost identical floor plans. (see old plans)
- The upper floor was renovated a few years ago. We currently live there.
- The ground floor is in an old, in need of renovation condition.
- Attic not developed, serves as a large storage room.
- Basement present with gas central heating

Goal:
Ground floor: Conversion of the ground floor so that ground floor and upper floor can be used together like in a single-family house. Connected living/dining area on the ground floor, small guest bathroom and hallway, study. Compare old and new ground floor plans.
Upper floor: The kitchen and dining room will together become a children's room. The toilet, bathroom and hallway should later be merged into a larger bathroom. Thus, the upper floor will only be used in the future for bathroom and children's/bedroom.

Here I show you two variants, which mainly differ in the arrangement of guest bathroom and hallway. I have marked the two waste pipes with red circles.

Who did the planning: draft by the architect, refinement by me.
What I particularly like: kitchen and dining room facing south directly onto the terrace, larger dining room, kitchen and dining room combined.

Specifically, I would like the following feedback or suggestions for improvement from you.

What do you think about placing the kitchen and dining room on the terrace side in the ground floor as shown in the new plans? Water/sewage connections for the kitchen are already present there. The walls between the old corridor/bedroom and the children's room/bedroom (cf. old ground floor plan) would be removed for this. A structural engineer has already given his OK for this.
The staircase must remain where it is, it could only be moved with very great effort.
The kitchen layout is only a suggestion. The kitchen can also be arranged differently. The old door between kitchen and hallway can be bricked up depending on the kitchen layout.
I am still quite uncertain about the hallway/guest bathroom area. Which of the two plan variants do you find better? Do you have other variants or ideas?
Is there anything you notice that I have overlooked? Are there any other improvements? What do you dislike?

I hope the information is sufficient. I look forward to your feedback.

I quite like the first solution. The hallway is not too big – rather the guest bathroom. In my opinion, the open hallway here is uncomfortable. I would separate the entrance area + hallway from the living area with drywall. I don't like your changes. They turn the study into a narrow corridor that doesn't need the space. The wardrobe is much more important.

Wardrobe cannot be too big!

However, in terms of layout, I would swap guest/office and kitchen (and then also swap dining and living). You currently already have the connections in the (old) kitchen, which can then be used. Where you are now planning the kitchen, the effort to lay the connections there is greater (= more costs). Also, the guest/office room would provide a separation between the entrance area and living space, which I personally would prefer. I also don’t find the access to guest/office through the living area ideal. Thought experiment: Grandma is visiting, goes to bed earlier, but needs to use the bathroom again and you might still be sitting in the living room with the neighbors. Not a nice situation for either side...

What have you planned for the staircase? At the moment, it is not connected to the living area, probably unheated and has the charm of a corridor in a medical office building, right? If I plan to connect the upper and ground floors, I would include the staircase in the design and possibly open it to the wardrobe. Is anything planned there? In my opinion, it’s too short-sighted to simply replan the two floors - they want and SHOULD be connected, in such a way that you no longer have the feeling of walking through a cold staircase from the sleeping area to the living area.

How is the house oriented? Does the terrace remain there? Is the entrance really through the garage? Should it stay that way? A site plan of the property with the rest ([driveway, garage, garden]) would be good.

You currently already have the connections in the (old) kitchen that can be used. Where you are now planning the kitchen, the effort to lay the connections there is greater (= more costs). In addition, the guest/office room would provide a separation between the entrance area and the living area, which I personally would prefer.

Exactly what I had already thought. On the other hand, the kitchen by the terrace is of course nicer. How difficult is laying the lines? It's not just water. The stove connection is also often a cable that doesn't run multiple times throughout the house.

Water/sewage connections for the kitchen are already available there

Sorry, overlooked. But still: I do not consider access for the guest through the living area desirable...