Methodology for the service life prediction of ceramic claddings in pitched roofs

Currently, the built heritage presents clear signs of degradation, requiring in some situations an urgent intervention. The majority of defects can be avoided or mitigated at the design and execution stages, but the designers and stakeholders often neglect the maintainability of the buildings and components, thus compromising their performance and durability. It is thus necessary to adopt an integrated approach during the buildings life cycle, evaluating their performance over time, the influence of the degradation agents and mechanisms on their durability and service life, and the adoption of cost-effective maintenance strategies. In this sense, it is crucial to use quantitative information related with the performance of building components over time. This study intends to respond to this need by proposing a methodology for the service life prediction of pitched roofs' ceramic claddings, which are the most common type of roofing system adopted in Portugal and in many countries around the world. These elements are one of the most vulnerable in a building, more exposed to the degradation agents, and with a higher incidence of defects. The method proposed is validated based on a visual inspection campaign, performed in 85 buildings and 146 claddings located in Portugal, with a total area of 43,991.6 m2. Various degradation patterns are established based on the roofs' characteristics, evaluating their influence on the roof claddings' service life. The proposed methodology allows obtaining coherent results, providing relevant information regarding the pitched roofs ceramic claddings' service life, aiding the adoption of rational and integrated maintenance strategies.