Energy refurbishment in the city center of Osilo, Sardinia (Italy)

ABSTRACT: This research develops the following hypotheses: a) sustainable cities can differ from the popular idea of hig-tech and low-density housing, surrounded by acres of green land: in fact calculations on heat dispersion, transportations, use of land, waste of materials, show the limits of this widespread image. b) the complexity in sustainable architectural design should be mastered through an interdisciplinary approach. c) technology retains chances of success not through optimization or advanced development, but through contextualization. The result is an investigation on the provocative concept that a kind of sustainable city is already here, disguised in the decay of the old city centres. The case study is Osilo, a small town in Sardinia, chosen for its compact urban fabric. The compactness of the settlement reduces solar gains in summer and heat dispersion in winter; proximity avoids fuel consumption; buildings refurbishment could prevent abandon and sprawl. In order to identify the potential of this little community as sustainable town, an interdisciplinary approach involved architectural design, building physics, materials technology, and urban planning. The study is based on data measured on the field: orientation, housing, microclimate, thermophysical properties of local building material, and energy-related behaviour of the population. The result is a set of proposals of appropriate technologies for the energy rehabilitation of the town, at both urban and building scales. A small pilot-project is currently under construction, and will be tested to prove the effectiveness of the concept.