The living wall system analysed in this study does not show -
for any of the three different scenarios assumed - any margin of
economic sustainability; the NPVs are all negative as well as the IRR
values which are not defined (as these do not exist; Table 7; Graphs
1 and 2). This vertical greening system has high installation costs
for the pre-vegetated panels and maintenance costs for the whole
system (panels to be replaces, plant species, irrigation system). Due
to these costs within the life cycle, after the initial costs for the
installation, the annual benefits overtake the annual costs (for
maintenance) of a few tens of euros, value which is insufficient to
pay back the incurred costs (Graph 3).