Development plan 1 full floor - upper floor?

Hello,

I ask for help in reading the B-Plan.
It states that only 1 full floor is allowed.
May 80% of the floor area then be used on the upper floor?

Example:
440 sqm plot, floor area ratio 0.2 -> 88 sqm floor area.
May I use 80% of this on the upper floor (88 sqm x 0.8 = 70.4 sqm as floor area)?

Thank you very much

Best regards, Arbeiter01

Floor area ratio of 0.2 results in 88 sqm of buildable area. You may of course add a habitable roof on top (provided there are no other regulations in the development plan). However, this must not be a full storey. Please look up the definition of a full storey in your state building code. You may also build over the entire living area of the ground floor with a roof; the definition of a full storey always refers to the average room height specified in the state building code. An attic is also possible in addition.

Is 80% allowed to be used as floor area on the upper floor?

I haven’t heard of 80%, rather 75% or 2/3, depending on the federal state. Is only the floor area ratio given and not the floor space index?

440 sqm x floor area ratio 0.2 would result in 88 sqm floor area; roughly estimated, I calculate 71 to 74 sqm floor space on the ground floor. I hope the floor area ratio applies only to the house, and the driveway etc. is allowed an additional allowance.

Thank you very much for your answers.
Landesbauordnung = Landes Bebauungs Ordnung?
88 sqm ground area is clear.
However, how do you get a floor area on the ground floor? Is there a formula for this?
Or a link where I can read about this well?
Thank you

Building regulations means LandesBauOrdnung (each federal state has its own).

How do you come to a floor area on the ground floor? Is there a formula for this?

very roughly estimated I calculate with 80 to 85%, which remains of the base area after walls. The smaller it is, the closer the truth lies to the less favorable value. These are only "approximate figures", which is why I leave out the decimal places to avoid creating the false impression of precise calculability (for three-digit values I therefore also round to half tens). This cannot be looked up, it is not a standard, rather empirically verified estimation.

Instead of "rule of thumb," in this size even "pi quarters" come close as a factor

Thank you for the information.