Passive thermography in the diagnosis of pathologies and thermal performance on building facades through a thermal camera installed on a drone. Preliminary approach in Coimbra (Portugal)

Abstract

Thermography is a non-destructive technique that allows the visualization of infrared radiation through visible thermal images and facilitates its realization at great distances from the surfaces under analysis, it can be considered quite advantageous in sustainability issues in urban rehabilitation. This technique allows, based on the results obtained, the development of more efficient solutions, such as more durable coatings and/or with greater insulation capacity, allowing the identification of pathologies that can hardly be detected by other methods, this allows maintenance timely, without the pathology of the material worsening. The measurements depend on different parameters that can influence the results, such as emissivity, the distance from the camera to the surface, the observation angle, reflectivity and color. In this case, for building facades, in addition to the above parameters, environmental conditions, solar radiation and wind predominate. The development of this preliminary study stands out fundamentally for its practice, from the collection, to the interpretation until the justification of the thermal data registered in several buildings. Regardless of the different conditions present on different days, it was possible to identify the constituent materials and record the different temperature patterns, such as the thermal transition between the same materials over the hours, orientation, exposure and different colors, and also the passage of masses of hot and cold air from inside the buildings to the outside. This work is relevant to a study base for implementing measures for greater urban efficiency in planning and ordering the territory and, consequently, achieving greater urban sustainability.