Análise de procedimentos de manutenção e manifestações patológicas em telhados verdes

Abstract

Green roofs are an interesting alternative to minimize the environmental impacts caused by civil construction in large urban centers. This technology, in addition to harmonizing the built environment with nature, provides visual aesthetics, improves thermal and acoustic comfort in the building, offers space for leisure and coexistence, grants natural habitat for animals and plants and is able to mitigate typical problems from large urban concentrations, such as air pollution and temperature increase due to the heat island effect. This technology can also reduce the surface runoff of rainwater, reducing issues with floods. Despite many studies addressing construction techniques and their advantages for the building, as well as for its surroundings, little has been studied about management and maintenance actions and possible pathological manifestations that can affect buildings with this system. In Brazil, this technology is still little used and, therefore, given the limited national experience, the motivation for this study arises, resulting in knowledge of the aspects for construction and post construction, contributing to the adoption of this technique in our country. For this purpose, a survey of the state of the art and the necessary procedures was carried out after its construction within the scope of its management and maintenance, with subsequent studies of the main pathological manifestations that can affect the green roof and consequently the building in which it is placed, as well as the construction techniques and practices recommended by international publications. Later, the field research method was applied to buildings with green roofs in the city of Belo Horizonte, MG, Brazil, with knowledge of the construction techniques and management and maintenance actions used, investigating and identifying possible anomalies reported in literature. Field studies were carried out between 01 / October / 2018 and 20 / August / 2019 and problems such as vegetation death, substrate compaction, areas without vegetation cover, vegetation advance, roots and rhizomes in protected areas, ascending and negative humidity and fissures in walls and in plateaus were found. Although the literature points to horizontal fences as the second constructive element to present the largest number of anomalies in buildings, on-site inspections have shown that the most recurrent problems in green roofs are concentrated essentially in the vegetation and not on the roof itself. However, the lack of periodic inspections with predictive, preventive and corrective maintenance plans can spread anomalies to the construction. Such procedures are essential for the system's longevity, raising the costs of its implementation.