Cool roof are very effective for the cooling and (excluding the
northern area of the basin) energy savings. Cool roofs are the most
effective solutions for the centre and southern areas of the Mediterranean
basin. Not insulated house might have excessive increase
in heating demand but, on the other side, cool roofs practically
may avoid the installation of the cooling systems, because of the
very low cooling energy demand. Low emittance cool roofs perform
worse than cool roofs, because of the reduced radiative losses
at night time, but improve the performance of conventional roofs.
For the same reason, metallic cool roofs have also limited heating
penalties respect to conventional cool roofs. They might represent
an acceptable compromise in the coolest Mediterranean area.