Linking vernacular architecture and environment: the case study of the Marche region (Central Italy).

The Marche region, in Center Italy, shows a rich heritage of traditional earthen constructions. The bulk of this patrimony had been formed between the XVIth and XXth centuries, when the sharecropping system was ruling the most part of rural lands. In Italy, earthen buildings have known rising and declining fortune, up to the second half of last century. The main argument against such an ancient method of construction was that it is utterly unsuitable when earthquake hazards are high. Furthermore, detractors claim on a commonplace which considers earthen buildings as unhealthy and beggarliness. Despite the rising evidences, brought along by ecological movements in architecture since the seventies, that raw earthen shelters elicit a healthy microclimate, the normative standstill in the Italian context has led to the abandonment of these vernacular construction techniques. In recent times, improvements in the shared sight of the European Commission aiming to mitigate soil sealing and to achieve no net land take by 2050, and the booming of bio-architecture, have risen the possibility to give new roles to the raw-earth. Amongst the different methods of vernacular architecture, raw-earth was a promising one under cultural, ecological, and economic points of view. Many authors studied the manifold aspects outlined by this method: history of predominant buildings, methods of inventory, social uses, building techniques and, recently, restoration of pre-existence constructions. In contrast, little attention has been paid to the relationship between artefacts and the surrounding environment, particularly the relationship between the characteristics of the soil in the close perimeter of the building, and the raw materials that compose the artefact. The bulk of this research aims to fill this gap and to strengthen the knowledge on the regional heritage of earthen buildings, considering both the different construction techniques and the specific environmental conditions where the buildings were settled. To this end, more than two hundred predominant buildings have been geo-located spread over the whole region. Subsequently, the database has been embedded with information on the lithological substrates upon which the houses were located. A set of samples of soils and building materials has been collected and characterised by lab analyses. The outcomes allowed us to characterize the materials composing the sampled earthen houses and to classify the artefacts into homogeneous groups. On a greater extent, shedding light on the relationship between artefacts and their environment, our research aims to contribute to improve the sense of place within the local community.