ᐅ Floor plan of a single-family home (1.5 stories, approximately 1,720 sq ft) adjacent to the existing family house of the parents

Hello everyone,

My husband and I would like to build a second house on my parents' property. The plot is 760 m² (8,180 ft²) in total and still has enough space to include a small garden. We obtained a preliminary approval from the building authority for a one-and-a-half-story single-family house with a pitched roof (that only took about six months…). To avoid using up the entire garden, we plan to attach part of the new house on the ground floor (currently the utility room) directly to my parents’ house. However, we are unsure if this is possible from a fire protection standpoint and whether we need to maintain certain distances. Ideally, we would like to keep the entire plot under my parents’ ownership and not subdivide it (it is a leasehold plot from the church with over 60 years remaining; the church will only give a statement if we submit a plan or idea of what we intend to do – which makes sense).

I hope I’ve included all the important details and basic ideas. If not, I am happy to provide more information. I look forward to your experiences, advice, and tips!

Zoning plan / Restrictions
Plot size → 759 m² (8,169 ft²) total (“our part” about half)
Slope → No
Site occupancy index → 0.4
Floor area ratio → 0.5
Building line, building window and boundary → The preliminary building approval specifies a minimum distance of 3 m (10 ft) to public traffic areas, all other zoning plan requirements must be met, and any necessary exceptions regarding the buildable area will be granted during the building permit process.
Edge development → Yes, desired carport and fence directly on the property boundary
Number of parking spaces → 1 parking space
Number of stories → 1.5 stories
Roof shape → Pitched roof
Maximum dimensions / restrictions → One side should be a maximum of 9 m (30 ft) long so the new house is not wider than the existing house
Other specifications → The angled corner of the lot is “problematic”; to maximize the use of the lot (3 m to the boundary), we would also angle the house. The existing parents’ house must also be considered (connect directly? Minimum distance? Fire protection?)

Homeowners’ requirements
Style, roof shape, building type → Pitched roof, otherwise fairly open
Basement, floors → 1.5 stories, no basement desired (high groundwater level!)
Number of occupants, ages → Family with one child, expecting two
Space requirements ground floor, upper floor → Ground floor: kitchen + dining area, separate living room, utility room, office that can later be used as a bedroom, bathroom with shower (ground floor should be designed to function as an independent apartment in old age) Upper floor: 2 children’s rooms, master bedroom (preferably with a small dressing area/room), bathroom
Office: family use or home office? → A home office is necessary
Guests per year → None
Open or closed architecture → rather closed
Conservative or modern style
Open kitchen, kitchen island → Kitchen island not essential, but a prominent counter would be nice
Number of dining seats → Four
Fireplace → No
Music/sound wall → Normal media wall
Balcony, roof terrace → No
Garage, carport → Carport
Vegetable garden, greenhouse → Possibly a small greenhouse later
Additional wishes / special features / daily routine, including reasons why or why not → There are many details (e.g. pantry next to the kitchen, access from kitchen to garden, utility room as a “mudroom,” office should not be next to living room because of noise, staircase not too close to the front door to allow easy entrance, etc.)

House design
Planning by → Do-it-yourself (Roomsketcher)
What do you like particularly? Why? → Using the angled corner of the house as a pantry (otherwise, it is difficult to find a good use for “that corner”), niche for the wardrobe, large utility room (we want to hang laundry in there too; is it too big?)
What do you not like? Why? → Kitchen maybe too tight? Too much hallway on the ground floor?
Price estimate according to architect/planner → Not available yet
Personal budget for the house including equipment → 300,000 €
Favored heating system → Underfloor heating

Why is the design like it is now? → See above

What is the key fundamental question about the floor plan in 130 characters?

Is the floor plan practical for everyday use, or are there major flaws that would be annoying? Are the rooms “large” enough or perhaps too large? Does it make more sense to build completely free-standing or is the idea to attach the utility room on the ground floor to the parents’ house good?