Floor plan single-family house with additional floor and roof terrace (115 sqm to 200 sqm)

Hello everyone,

we have purchased a detached house with the attached key data and are planning to expand the property in order to create an extension in the existing 1st floor (conversion of the terrace above the garage into living space) and an additional floor of an attic with a roof terrace.

We are now wondering whether our planning achieves a sensible room layout for the 1st floor or if there might be other sensible room layouts. We would also appreciate further inspiration for our attic.

Development plan/Restrictions
Property type: Detached house Living area: 118.93 sqm Usable area: 57.57 sqm Total area: 176.50 sqm Plot size: 390 sqm Year built: 1970 Energy source: Oil Heating type: Central heating Number of floors: 2
Parking spaces: Garage and outdoor parking space Basement: yes, fully basemented
Maximum height/limits -> 2 full floors, maximum height not known
There is no development plan, therefore according to § 34 of the Federal Building Code the neighborhood development applies. Here we have learned that we are allowed to add 2/3 of the 1st floor as an additional storey.

Room layout ground floor (no changes planned)



Room layout 1st floor OLD


Room layout 1st floor NEW: Conversion of terrace above garage into living space and new staircase to 2nd floor / attic


Room layout attic / 2nd floor


Many thanks and best regards!

What is the question, why the thread? What is your concern? (Ps: who sees pictures? Only I see one)

Short question. Do you also have a picture / a drawing with the property boundaries? Asking because of the setback distances. If the shown picture also depicts the property, it will already be more difficult with the extension on the garage because of the setback distances.

Aside from that, I think the upper floor is a disaster. Actually, I am more the financer than the planner, but I still have a few comments.
- Bedroom monstrously large – especially compared to the children's rooms
==> do you live in the bedroom?
- Balcony at the bedroom is wasted money if you have a garden
- Angled lower children's room practically unusable
- Second bathroom is a second guest WC? Which bathroom do the children use?

To compensate for the too small rooms on the upper floor, there is an "Other Room" as a ballroom in the attic with a huge terrace?

In summary: I do not understand the planning.

For the space planning and assistance, you should fill out the questionnaire. That helps everyone involved.

I can only agree ... children's room with a hose extension that is not 180 cm wide ... what is supposed to happen there? And I also think that due to boundary building regulations, the extension on the garage is not allowed. Presumably, the current complete use as a terrace is already not entirely permissible.

Is an architect involved?

On the phone, I also see pictures: In short: the garage is edge development if it is under 2.5 or 3 meters in the border area, and therefore an extension is not possible there, at least not in that size. 3 meters must remain to the neighbor.