Floor plan optimization, renovation of a two-family house into a single-family house, built in 1957

Dear forum members,

I have been reading in various sections for some time and have already been able to use many very helpful pieces of information – thank you for this!!

We have bought a two-family house built in 1957, which we want to completely renovate (energy-efficient refurbishment + interior work) and use as a single-family house.

We are very happy about help and constructive criticism regarding the floor plans!

Here is the slightly modified questionnaire:
Bebauungsplan/Einschränkungen
Size of the plot: 454sqm
Slope: yes
Edge development: no
Number of parking spaces: 1 garage
Roof shape: gable

Anforderungen der Bauherren
Basement, floors: basement + 2 full floors + attic to be partly converted
Number of people, age: 3 persons, 32 years, 38 years, and 10 months
Room requirements on the ground floor, upper floor: ground floor – living, dining, kitchen, WC
Upper floor – 3 bedrooms + bathroom
Office: office for 2 necessary, partly for home office planned in the attic
Guests per year: 3 times a year
Open or closed architecture: rather closed, based on conditions
Open kitchen, cooking island: closed kitchen is also okay
Number of dining seats: 4–6
Fireplace: yes
Music stereo wall: no
Balcony, roof terrace: yes
Garage, carport: garage available, additional parking space to be created

Hausentwurf
Who is responsible for the planning: do-it-yourself
What do you like in particular? Why?
Upper floor results in regular rooms and a sufficiently large bathroom, orientation of living and dining area to the south side towards the garden with large window fronts
What do you not like? Why?
Arrangement of hallway, guest bathroom, kitchen including doors and access on the ground floor "complicated," kitchen may be open or closed, should not be a constant thoroughfare, is the loss of the two-family house character sufficient?
Price estimate according to architect/planner:
400k – 500k
Personal price limit for renovation, including equipment: 500k
Preferred heating technology: air-to-water heat pump with photovoltaic

What is the most important/fundamental question about the floor plan summarized in 130 characters?
Does the two-family house character get lost by opening the staircase on the ground floor with a glass door/front? How can the hallway, WC, kitchen area on the ground floor be optimally designed?

Attached are the original construction plans according to the current state and the plans/ideas we have created so far.

Many thanks and best regards

I simply will not understand ... why, if you want answers, can't all floor plans at least be aligned uniformly?

I just won’t understand ... why can’t all floor plans be aligned uniformly when you want answers?

Because then it would be hard to read anything. Unfortunately, it’s hardly possible anyway. I don’t see the entrance. Is it supposed to be relocated?

Thank you for the quick responses.

Sorry, this is my first post here. Should I upload all images in better quality? What is hard to read – original plans or our design?

The house entrance is located at landing level between the basement and the ground floor and is therefore not shown. Thanks for the note. We had not planned any relocation.

In my opinion, this is not a renovation with 500k.

Ground floor: A structural engineer should definitely propose a solution for how the wall between the living room and bedroom can be removed. The same applies to the kitchen wall. The staircase is designed as a windbreak. I would not remove the door. The entrance will probably remain at half the height.

Attic: I would not change the bathroom much, just replace the bathtub with a shower. Having a separate toilet is not a bad solution. The wall to the former kitchen in the bedroom should hardly be a problem in my opinion. Your structural engineer will tell you how to proceed.

If you are already so skilled with the planning, then do it properly. Draw the changes in the plan. Demolition in yellow and new in red.

That way you don’t have to rotate all your plans. Please make neat screen prints so that one can read something.

Today, every single-family house looks quite similar anyway. A lot can be improved with the facade design.

Thank you for taking the trouble to look over it despite everything!

A structural engineer will come in about 2 weeks. We have "planned" that the 11.5 cm walls can be removed, if necessary with a beam, and the 17.5 cm wall is rather complicated to open, or openings there should preferably be kept narrow.

The idea at the entrance to the ground floor was to widen the passage and possibly close it with a glass door/ glass element. On the one hand to provide thermal insulation, but above all to somewhat reduce the character of a two-family house visually through the glass element.
We are mainly unsure how to arrange the wardrobe, WC, and kitchen sensibly and where to create access points/ openings/ doors.

I will browse the tool to see how I can color walls red and yellow, then I will try to create an optimized all-in-one plan.

Regarding financial planning, we had three architects, two of whom estimated at least 500k and one at 600k as a preliminary estimate. A construction manager (authorized officer at a developer) estimated 400k. The house is largely in the condition of its year of construction.