A single façade (south oriented) with a vertical greening system
can reduce the energy demand for air conditioning in Mediterranean
climate depending on the type of external walls: in the case
where the wall (30 cm of concrete) is externally insulated with
15 cm of polystyrene, the values of energy saving for cooling are
between 1.4% and 2.6% compared to a non green case. In a second
case scenario with an internal insulated wall (with 15 cm of polystyrene
with 30 cm of concrete) the presence of a green layer leads
to a reduction in cooling energy consumptions from 4.7% to 6.2%.
With a massive wall with 40 cm of concrete (non insulated) the
cooling energy reduction that can be obtained is up to 65.8% [14].
According to Ottelé [37] insulation material moderates the prevailing
temperature’s difference between the outside and inside, as
it is possible to conclude according to the results obtained by Mazzali et al.