Traditional Construction Techniques Revaluation of «Good Practice Rule» for Sustainable Construction

The Mediterranean area has been characterised, since ancient times, by technical knowledge and stylistic exchange influences. Migrations, conquests, commercial links allowed more advanced constructional cultures to spread, in different historical periods, even at relevant geographic distance and beyond the Basin itself. During European Middle Ages, as instance, the weight of Roman art on Romanesque architecture in France, Byzantine influence on figurative and decorative arts in Germany, France and Italy, Islamic art rule in Southern Spain and Southern Italy can be cited. Multicultural contact European territories like Southern Spain and Italy were interesting demonstrative laboratories of imported techniques adoption and combination, as well as of styles amalgamation (mudejar art). In such contexts, foreign good technical rules have been locally assumed by adapting materials and accustomed practice. Such variations can be seen as the consequence of a process of optimisation of material and economic resources which entails what we could presently call “improvement of sustainability performances”. Since the Renaissance, and more systematically since XVIII century, the habit began to classify architecture constructional and formal rules in treaties and manuals. The Grand Tour, the Grand Prix of Rome1 and afterwards more frequent and southwards travels in the Basin, had permitted direct observation, study and representation of Mediterranean buildings in Voyage Carnets. They were drafted in detail and hypothetically reconstructed by scholars and Beaux Arts academy students2 interested in ancient Greek and Roman construction issues but also in vernacular examples. Manuals and treaties contain a precious structured repertoire of information on common traditional techniques in the Mediterranean basin. Up to the I World War, French and Italian textbooks - the present study refers to some of them, - endorsed architectonic identity of local examples that were directly surveyed with reference to analogues applications in ancient well known buildings. Local idiom were codified in these “illustrated dictionaries of construction art”, where classical universal rule is taken into account too. Furthermore they give details on durability and quality of different materials and techniques and putinto-work practices, references to cost and material depletion and use optimisation. At any rate transportation, material availability, recycling and recovering concerns were always dealt with in pre-modern building contracts and documents. The paper investigates some issues of “sustainability” which were implicit in traditional techniques of construction by taking into account prescriptions in manuals and existent case studies. Local traditional rules, only partially deducible from manuals, are to be integrated, in fact, by data coming from direct survey in order to verify local variations, efficacy and related durability performances