Estudo do estado de conservação de fachadas históricas em Lagarto-SE: avaliação em exemplares religioso, institucional e residencial

Abstract

The conservation of built cultural heritage—particularly in inland towns—faces a disconnect between the recognition of its historical, aesthetic, and identity-related value and the actual implementation of safeguarding measures, a situation exacerbated by a scarcity of systematized technical studies. Against this backdrop, this dissertation aimed to assess the actual state of conservation of the rendered facades of historic buildings in Lagarto, Sergipe (SE), using an integrated approach that links architectural characteristics, construction techniques, constituent materials, and pathological manifestations. Three representative examples of distinct typologies, built between the 19th and early 20th centuries around the Praça da Matriz, were selected: the Colonial Residence at No. 175 (wattle-and-daub construction); the Church of Our Lady of the Rosary (Neo-Gothic style, stone masonry); and the former City Hall (stone masonry). The methodology comprised a literature and document review, architectural analysis, laboratory characterization of mortars (visual and petrographic analysis, particle size distribution, soluble salt testing, and X-ray diffraction), visual inspection with damage mapping, infrared thermography, and the application of the Conservation Status Indicator for Historic Building Facades (IDh). The results revealed a critical state of conservation across the evaluated group and allowed for the distinction of two material families—historic air-lime mortars (in the Residence and the Church) and contemporary cement-based repairs (in the City Hall)—as well as three predominant degradation mechanisms: structural (due to settlement) in the Residence; physicochemical (due to rising damp and salinization) in the Church; and material incompatibility (due to non-conservative interventions) in the City Hall. The application of the IDh index confirmed this scenario, with values ranging from optimal (9.60% on the church's north façade) to very poor (776% at the Residence and up to 243% at City Hall), demonstrating that the most severe degradation is systematically associated with the replacement of original materials with rigid, impermeable cement-based mortars. It is concluded that an integrated technical diagnosis not only quantifies degradation but also identifies its root causes, providing a scientific basis for compatible interventions that respect the authenticity and integrity of Lagarto’s built heritage and inform future municipal preservation policies.