APPLICATION OF PASSIVE INFRARED THERMOGRAPHY TOWARDS THE IDENTIFICATION OF FACADE DEFECTS IN A TROPICAL CLIMATE

Abstract

Infrared Thermography (IRT) is a non-destructive testing (NDT) tool prevalently used to identify anomalies on building façades for several decades. However, it’s applicability in tropical climatic conditions are understudied despite the significant role meteorological conditions play in affecting the thermal images produced by the IRT device. In Singapore, the government is looking into alternatives to improve the efficiency of façade inspection through the incorporation of drones and Artificial Intelligence (AI). This is in tandem with the potential of a compulsory façade inspection regime being introduced for buildings over 13 metres high and 20 years of age to combat the rising spate of falling façade incidences within the recent years. Thus, IRT may be integrated to enhance the detection capability during the inspection process.

A case study approach was used where clusters of Housing and Development Board (HDB) flats were selected due to its prominence, and common defects on concrete with plaster and paint finishes were chosen for further investigations. Thermal images at specific intervals throughout the day were taken of the anomalies to identify the ideal timing where maximum contrast can be seen together with considerations of the climatic and weather conditions on-site. The deliverables of the study consist of the identification of ideal timings to capture the thermal images of the defects while considering the distinct sets of tropical climate conditions such as long sun exposure hours, constant high temperatures and relative humidity. In addition, specific guidelines were provided for façade inspection, specifically in the Singapore context, that may be adopted for future use. In conclusion, several parameters affect the capability of IRT usage for defects identification. These include the natural climatic factors, site weather conditions, façade orientation of the defect, hindering surrounding objects and the IRT device used in terms of its settings and operation. If these factors are addressed adequately, the implementation of IRT for façade inspection is viable. However, additional NDT tools may be further utilised to supplement IRT in providing more information on the severity and depth of the anomaly. Moreover, extrapolation of findings to other types of façade materials must be taken with caution where further exploration may be made in future studies.