Variations in the applicability of infrared thermography for detecting defects in different facade coatings:

a systematic review

Abstract

Objective – Identify variations in the applicability of infrared thermography (IRT) for detecting defects in different façade coatings, identifying challenges and trends in the field.

Methodology – A Systematic Literature Review (SLR) was conducted based on the PRISMA protocol. The selection included 43 articles, analyzed from 394 studies imported using a search string in the Science Direct, Scopus, and CAPES Portal databases, covering the period from 2018 to 2024.

Originality/Relevance – The study addresses the theoretical gap regarding the application of IRT in façade inspections with different types of coatings, highlighting its role as a non-destructive diagnostic tool. The academic relevance lies in the systematization of variables that affect the technique's reliability, considering different coating materials and environmental factors.

Results – The research identified that IRT is widely used for inspecting ceramic, mortar, and stone coatings, with less frequent application in reinforced concrete. The technique's effectiveness is influenced by factors such as solar radiation, humidity, and material emissivity. To optimize results, a minimum temperature difference of 10°C between indoor and outdoor environments is recommended. Additionally, complementary techniques such as ground-penetrating radar (GPR) and advanced image processing are necessary to enhance the reliability of defect detection.

Theoretical/Methodological Contributions – The study highlights the challenges of IRT applicability in different coatings, emphasizing that: (i) in ceramic coatings, porosity and humidity affect detection; (ii) in mortar coatings, material heterogeneity impacts results; (iii) in stone coatings, mineralogical variability interferes with analysis; and (iv) in reinforced concrete, high thermal absorption can mask defects. Furthermore, it underscores the importance of controlled environmental conditions and the use of complementary techniques for greater accuracy.

Social and Environmental Contributions – The application of IRT in façade preventive maintenance contributes to the sustainable management of urban infrastructure, enabling non-destructive inspections and continuous monitoring of building conservation status.