Thermography Applications in the Study of Buildings Hygrothermal Behaviour

Infrared thermography (IRT) can be defined as the science of acquisition and analysis of data from non-contact thermal imaging devices. The process of thermal imaging has simplified over the years with the availability of efficient, high resolution infrared cameras that convert the radiation sensed from the surfaces into thermal images (Rao, 2008). Thermography literally means “writing with heat”, just as photography implies “writing with light”. The invisible infrared radiation emitted by bodies is converted into temperature and displayed as thermal images, the thermographs. Infrared thermography is a powerful tool for engineers, architects and consultants for use in evaluating existing buildings and structures. Infrared thermography is a fast and reliable tool to assist in identifying potential problems in existing buildings. Infrared thermography offers several advantages in condition surveying. Recent developments in thermography and image processing made the technique a valuable addition to the repertoire of nondestructive testing methods. Thermography is a non-contact, non-destructive technique. While the potential exists, thermography has not yet been utilized extensively in the assessment of monuments and ancient structures. Condition surveys by conventional techniques cannot detect the presence and source of moisture readily, require access to the surfaces, and are expensive and time consuming. On the other hand, IRT offers a rapid method for assessing large surfaces without the need of a scaffold to reach the area under investigation.