Historic tuff masonry in Naples: different approaches to its conservation

[EN] Tuff, a sedimentary rock made of volcanic ash, is a traditional building material in the Campania region. Since its foundation Naples’ architecture, whether monumental or vernacular, has been erected in tuff masonry and only the arrival of concrete and steel has meant its downfall. Due to the soft nature of tuff, traditionally the building material was designed to be covered by plaster and very few and monumental architectures, by selecting and sculpting to the purpose the rock, were designed to be fair-faced. In years the exposition to natural and artificial degradation agents has brought a wide variety of deterioration phenomena both on the fair-faced tuff masonry and the ones that had lost plaster. In approaching the restoration of these architectures, the conservator is faced with a challenging task. This is due to the difficulty of balancing the pursue of minimum intervention and authenticity respect, the conservation of the historic consolidated image of the architecture and the necessity of using the best restoration techniques that guarantee the highest conservation of the material in future years, with particular regard to bio-compatible and sustainable materials both for operators and the environment. By analyzing the restoration of various architectures, both archaeological and modern, the paper will address this difficult task and the different decisions made by the conservators in relation to the monuments’ nature, identity, history and status of conservation. The paper is based on a multidisciplinary approach due to the contribution of the expertise of an architect, a restorer and an archaeologist.