The categorisation per building as “intensively” or “extensively greened” is carried out based on the predominant component. If a building exhibits a greened roof area of > 50 % “extensive”, the entire greened roof area enters into the calculations as “extensive”.
Analyses on three spatial levels will be shown in the following – building, block and block segment of the ISU and borough.
The buildings were classified into six categories of building use based on the ALKIS and NOT-ALK use. Table 2 and Figure 3 show the order of magnitude and percentages of the building uses covered with green roofs.
The greened roof areas [m2] are relatively evenly distributed across the different building uses “Residential” (including weekend cottages), “Non-residential buildings” (e.g. schools, town halls, retirement homes, administrative buildings), “Office buildings, commercial” and “Underground car parks without overlying buildings” with percentages between 20 and 25 % (Fig. 3).
In addition, Table 2 indicates possible potentials for future green roofs. The building use “Office buildings, commercial”, which presumably has a high proportion of flat roofs, only has greened roof areas on 2.7 % of the buildings to date. A high potential for green roofs can be assumed here. By contrast, this potential is much more intensely utilised at 80 % in the case of underground car parks, as expected, albeit with different proportions of greening on the individual roof areas of greened underground car parks.