Retrofit of Massive Buildings in Different Mediterranean Climates. Inter-actions Between Mass, Additional Insulations and Solar Control Strategies.

In temperate climates, such as in most parts of Italy, it is necessary to limit both winter
heat losses of buildings and their overheating in other periods. Moreover, in warmer
Mediterranean climates the convenience of insulation against the building’s thermal
inertia must also be evaluated. Therefore, when the energy renovation of an old
building with heavy masonry is performed the problem is to optimize the position and
the thickness of the additional insulation. In presence of extended glazed surfaces, the
most appropriate solar control strategy should be defined too. Both issues are present
in many old Italian public buildings.
This paper deals with a computerized methodology for optimizing these choices by
taking into account the interactions between thermal mass, additional insulation as
well as internal and solar gains. The case study consists in a typical school building from
the early 1900s. Building’s thermal behavior was simulated in different Italian climates:
Bologna, Roma and Palermo. The effects of various solutions on energy demand and
comfort were compared. The possible effects of different types of masonry, different
building’s orientations and various intended uses were also explored.
Simulation results show that the optimal intervention strategy, for the considered type
of building, depends not only on the climate but also on the building’s intended use,
which determines the internal gains and the time profile of use.