Convert the garage and additionally create living space

We have bought a house (semi-detached house) and the current living space (60 sqm) is just small for us. The house was built sometime in 1930 and the garage sometime in 1965. The house is built on 2 floors, downstairs kitchen, living area and upstairs bedroom and another room. However, the ceiling height on the upper floor is not very high. There is also an attic, which has not been converted at all. We want to convert the garage and the courtyard into living space. I have attached a sketch here. We might also add a storey to the garage and install a staircase in the current courtyard.

If that works out, we would combine the current kitchen with the living area so that the kitchen becomes bigger.

Could you please explain to me what we will face (e.g. building permit, do we have to hire an architect, etc. etc.)? I would also like to know financially how much it would cost us.

Oh,
the black line is the current state and the red line is our plan....

Hello,

Could you please explain to me what lies ahead (e.g. building authority approval, do we have to hire an architect, etc. etc.)?

first of all, it should be clarified whether an extension is even possible. It’s best to run to the building authority and clarify. (--> floor area ratio, floor space index, setback distances, etc.).

For such a project, I would also bring an architect on board.......

Cheers

Thanks for the comment, I will walk over there tomorrow....

I believe a building permit is mandatory. Only thing I’m still thinking about is how to add an extra floor to the garage. In the building plans for the garage from 1964, it states that they dug 1 meter into the ground, whether that is an advantage I cannot say.

What would you think, would it be possible with the garage and an additional 1st floor above it with a staircase in the courtyard (New hallway)?

I also have absolutely no idea about the costs....

Regards,
Juliet

I have revised the sketch and attached it again.

Maybe it is clearer now.

Thank you for your tips.

Regards,

Juliet