The plan before 1996, the concret (beton) is marked yellow.
The room to the south is not cut yet.
the pictures shows 61 sqm concrete (bet) terrace   in 1996 the MA37 prescribed removal of the concrete (bet) terrace
 
     

 

The plan from 1996 prescribing the allowed  (on condition to be revoked) construction, see the Terrace and Flugdach
Concrete (bet, beton) was not removed
Even the latest demolition 2018 has not removed all beton
 

 

  b1996