Floor plan design for a single-family house approximately 125 sqm, 2 full floors

We want to build a single-family house of about 125 sqm. Our wish is to integrate a small study in the upper floor.

We prefer not to have the staircase directly next to the front door so that we don't always have to walk through the "dirty area." However, an L-shaped staircase (then next to the front door) would probably save space. The utility room could thus be correspondingly larger (then move the front door slightly).

The arrangement of the kitchen cabinets is not yet final. A place for the fireplace is also still missing (the problem here is to accommodate the chimney in the upper floor).

Development plan / Restrictions
Plot size 1000 sqm
Slope approx. 1 - 1.5 m gradient from north to south over 50 m.
Floor area ratio / Plot ratio unknown due to §34
Building window, building line and boundary Building window 5 m from the street in the north, approx. 20 x 20 m, in the west there is a 15 m distance to the neighbor’s building window, i.e. the minimum distance to the western neighbor is 15 m, see site plan.
Edge development -
Number of parking spaces -
Number of floors I-II
Roof shape / Style / Orientation no restrictions
Maximum heights / limits -

Requirements of the builders
Style, roof shape, building type City villa, hipped roof or pyramid roof
Basement, floors without basement, 2 floors
Number of persons, age 3 (33, 33, 3)
Space requirements on the
Ground floor: living/dining room, kitchen, utility room, WC
Upper floor: bathroom, bedroom, child’s room, work, guest/hobby

Office: Family use or home office? Home office
Overnight guests per year 3-4
Open or closed architecture,
conservative or modern design classic
Open kitchen, cooking island semi-open, possibly cooking island
Number of dining seats 4-6
Fireplace yes
Music/stereo wall -
Balcony, roof terrace -
Garage, carport: Carport
Utility garden, greenhouse -

House design
Planning by: > Do-it-Yourself
What do you like especially? Why?
What do you not like? Why? North and west views look a bit odd, maybe an additional window should be integrated there.
Personal price limit for the house, including equipment: approx. €250,000
Preferred heating technology: Gas or air-water heat pump

If you have to do without, which details/extensions
-can you do without:
-can you not do without:

Why is the design the way it is now? For example,
Various floor plans from prefab house providers/GUs from the internet served as templates.

What is the most important/fundamental question about the floor plan summarized in 130 characters?

The following questions:

1. Is the floor plan easy to implement and practical in use?
2. Prefer an L-shaped staircase to save space?
3. Do load-bearing walls in the upper and ground floors have to align?
4. How to best position the carport on the plot, in the northeast or northwest?
5. How could the chimney for the fireplace be integrated in the upper floor without taking up too much space?

Floor plan:


Location:


Carport arrangement:

The utility room is too small to also be a [HAR], and definitely not suitable as a cellar substitute. But if you understand the whole thing only as a sketch despite the dimensions, it is quite a decent start.

First, I think two fundamental questions need to be clarified. 1. With 9m x 9.60m, you are at about 135-140m². Calculating the upstairs hallway at only half does not help. If you have set the 125m² because of a price limit, then you already have a problem. 2. What heating system is planned? With a small area, savings are always made at the HAR, which I personally consider wrong, but be that as it may. So you should consider what absolutely must go in there. With 4m², the washing machine & co definitely have to be housed elsewhere (kitchen / bathroom?), and even then it is questionable whether the technology has enough space.

1. With 9m x 9.60m you are at about 135-140m². Calculating the hallway upstairs only half does not help. If you set the 125m² because of a price limit, then you already have a problem. 2. Which heating system is planned? With little space, savings are always made in the utility room, which I personally consider wrong, but never mind. So you should consider what absolutely has to go in there. With 4m², washing machine & co definitely have to be accommodated elsewhere (kitchen / bathroom?), and even then it is questionable whether the technology has enough space.

For the exterior dimensions, we oriented ourselves on other floor plans. The 125sqm is intended as a guideline; the house should not be significantly larger (more than 10sqm additional), also for cost reasons. How did you calculate the 135-140sqm? When I add up the individual rooms, I get about 128sqm without considering the stairs. We have not yet decided on the heating. Possible options are gas or an air-water heat pump. Are there big differences between the two systems regarding space requirements in the utility room? If we do take a stairway in L-shape, we can move the front door and enlarge the utility room a bit. What do you think of the following floor plan: Upper floor accordingly changed with adapted bedroom:

I am afraid the utility room is still very cramped. And I would probably swap the children's room and the bedroom upstairs. You probably spend less time in the room than the child, who also has the desk in the room.