Some data about traditional Venetian building materials characteristics

In Venice urban context, building materials are placed in contact with water on a permeable soil, with high quantity of salt aerosol, brushed by salt water and exposed to air with high level of relative humidity throughout the entire year. As a consequence, water can penetrate porous material by different processes such as vapor condensation, rain washout, drying-wetting cycle, capillary rise and operating humidity. These factors generate aesthetic, hygienic, thermal and mechanical damages. Materials and structures are subjected to deposition, surface alteration and fragmentation, internal erosion and dissolution. These damages can be avoided through designing and planning proper interventions, at the basis of which a complete knowledge about materials characteristics and behaviors is fundamental. Almost all Venice buildings have a masonry structure with clay bricks and lime mortar, and in some cases Istrian limestone as a structural part or decoration element. As a first step in this analysis, clay brick and lime mortar were considered. Many studies starting from the two edition of the conference “Il mattone di Venezia” in 1979 and 1982 supplied useful information but often unlinked among them. In this context the aim of this study is to collect and present chemical and physical data from previous studies of the past decades, related to traditional buildings materials in Venice lagoon. Usually in fact, characterization is developed in each specific research only from a specific point of view and it is seldom complete for a single material. On the other hand, this information are of basic importance for the design and realization of sounded restoration and conservation activities.