ᐅ Building on the Plot – To Include a Basement or Not?

Hello everyone,

maybe this thread is a bit early since we don’t have a planned floor plan yet. But we would still appreciate your advice. First of all, because this is probably the most important information: We are planning with a budget of 600,000 euros for the house plus additional building-related costs. We have received approval to purchase the plot shown here. We will sign the purchase contract at the end of next week. Now to our problem:
We are very uncertain about which is the better decision for our plot: a (partial) basement with a smaller floor plan (about 130 – 140 m² (1400 – 1500 sq ft)) (Option A), or a slab foundation with a slightly larger floor plan (about 170 m² (1800 sq ft)) (Option B).
I will list the pros and cons as we see them for each option.

Option A:
+ Utility room in the basement frees up space on the ground floor; no noise issues
+ More usable space overall
+ Hobby room can also be used flexibly for gatherings
+ Storage space!
+ Possibility of a double parking space
- Expensive (a full basement is probably unrealistic with our budget; is a partial basement more sensible?)
- Less space on the ground and upper floors

Option B:
+ More living space on the ground and upper floors
+ High potential for cost savings!
+ Possible to use the attic for storage?
- Is there still enough space for a double parking space?
- Possible issues with the plot ratio? If we understand correctly, the footprint of the house may be limited to 143 m² (1540 sq ft) plus 70 m² (750 sq ft) for driveway, garage, etc. My feeling is that the developed area might easily be underestimated and reach the limit quickly.

We would be interested in your opinion on how you would build on this plot. I have made a very rough sketch of how we imagine the orientation of the house and placement of parking spaces, etc. I have also attached the site plan and development plan. The questionnaire is mostly filled out, but a “final” floor plan is still missing, as mentioned. This will also largely depend on the question of whether to have a basement or not.
I hope I haven’t forgotten anything...
Best regards

Development Plan / Restrictions
Plot size 477 m² (5130 sq ft)
Slope Minimal
Plot ratio (ground coverage ratio) 0.3
Floor area ratio 0.8
Building envelope, building line, boundary 14 x 14 meters (see image)
Edge development see image
Number of parking spaces unknown
Building height up to 2 full stories
Roof type Hip roof or gable roof 30-40 degrees
Architectural style unknown
Orientation unknown
Maximum height / limits unknown
Other requirements unknown

Homeowners’ Requirements
Architectural style, Roof type Gable or hip roof (open to either)
Basement, number of floors Basement yes/no is the big question. 1.5 – 2 full stories
Number of occupants, ages 2 adults (32 and 33), 1 child (1), 1 more child planned
Room requirements on ground and upper floors Utility room, guest toilet with shower, guest room, study (a study nook might also be sufficient), 2 children’s rooms, master bedroom, bathroom
Office: family use or home office? Both
Overnight guests per year Parents-in-law should be able to stay regularly (about once a month)
Open or closed layout Open kitchen / living / dining area
Conservative or modern design Exterior should be clean and simple – relatively straightforward
Open kitchen, kitchen island Yes, at least a peninsula
Number of dining places in the kitchen No dining space needed in the kitchen; the dining room should have space for a large table
Fireplace If budget allows; not mandatory
Music / sound wall 11.2.4 sound system + TV to be integrated into the study (or guest room)
Balcony, roof terrace Not necessary
Garage, carport Double carport or double garage would be nice if space allows; otherwise 2 parking spaces in tandem
Utility garden, greenhouse Not planned
Other wishes / special features / daily routine, including reasons why some options are preferred or rejected Smart home with KNX (or Loxone); controlled ventilation system, photovoltaic system (+ possibly battery storage), air-to-water heat pump

House Design
Who did the planning:
- Planner from a construction company
- Architect
- Do-it-yourself
What do you especially like? Why?
What do you dislike? Why?
Estimated cost according to architect/planner:
Personal budget limit for the house, including equipment:
Preferred heating technology: Air-to-water heat pump + photovoltaic system (+ possibly small battery storage)

If you have to give up something, which details or features
- can you do without:
- cannot do without:

You have already answered your own question. With the floor area ratio, the house is only allowed to have a footprint of 143 m² (1,538 sq ft). Therefore, the 170 m² (1,829 sq ft) plan without a basement is not permitted.

I don’t quite understand... The 170 m² (1830 sq ft) refers to the living area, not the footprint. For example, if I consider a house measuring 12 x 9.5 meters, the footprint would be 114 m² (1227 sq ft), right? Or do you mean that it’s unrealistic to fit all other structures like the garage, terrace, driveway, etc., within 100 m² (1076 sq ft)?

SandyBlack schrieb:

I don’t quite understand... The 170 sqm (1830 sq ft) refers to living space, not the building footprint. For example, if I consider a house measuring 12 x 9.5 meters, the footprint is 114 sqm (1227 sq ft), isn’t it?
Or do you mean it’s unrealistic to include all other structures like the garage, terrace, driveway, etc., within 100 sqm (1076 sq ft)?

The floor area ratio indicates how many square meters of your plot you are allowed to cover with building footprint, meaning the area sealed by the building. It does not refer to living space. Ancillary areas are usually permitted to exceed this by 50%. Therefore, option B with 170 sqm (1830 sq ft) is not feasible.

Myrna_Loy schrieb:

The floor area ratio indicates how many square meters you are allowed to build on the plot, meaning the area you can cover with building structures. It does not refer to the living area. Ancillary areas are usually permitted to exceed this by 50%. Therefore, option B with 170 sqm (1830 sq ft) is not feasible.

I believe she means 170 m² (1830 sq ft) spread across the 2 floors. That should be acceptable.

The 170 sq m (1,830 sq ft) would then be spread over 2 floors.

Unfortunately, all three plans lack a north arrow, and each plan is oriented differently.