Time-lapse thermography for building defect detection

Abstract

a b s t r a c tBuilding thermography traditionally captures the thermal condition of building fabric at one single point in time, rather than changes in state over a sustained period. Buildings, materials and the environment are, however, rarely in a thermal equilibrium, which therefore risks the misinterpretation of building defects by employing this standard methodology. This paper tests the premise that time-lapse thermography can better capture building defects and dynamic thermal behaviour. Results investigating the temporal resolution required for time-lapse thermography over two case study houses found that under typical conditions small temperature differences (approximately 0.2 K) between thermal areas could be expected for 30-min image intervals. Results also demonstrate that thermal patterns vary significantly from day-to-day, with a 2.0 K surface temperature difference experienced from one day to the next. Temporal resolutions needed adjusting for different types of construction. Time-lapse experiments raised practical limitations for the methodology that included problems with the distance to target and foreground obstructions. At the same time, these experiments show that time-lapse thermography could greatly improve our understanding of building transient behaviour and possible building defects. Time-lapse thermography also enables enhanced differentiation between environmental conditions (such as clear sky reflections), actual behaviour and construction defects, thereby mitigating the risk of misinterpretation.

Understanding the Human Factor of the Energy Transition: Mechanisms Underlying Energy-Relevant Decisions and Behaviors

“…Colors represent different temperatures and allow inferences where heat, and so energy, might be conserved in buildings. Unexpected areas of heat escaping from the building or cold air entering are made visible (Pearson, 2011;Fox et al, 2015).…”

Building defect detection: External versus internal thermography

“…This was likely due to differences in wind, solar loading and rain exposure effecting one side of a street more than another. Furthermore, work undertaken by the authors [5] illustrates the effects that transient climatic changes can have on heat transfer through materials and thermal image interpretation. This therefore raises questions over the ability of a fast methodology to collect meaningful image data that can be used to assess (qualitatively or quantitatively) overall thermal performance and defects in buildings effectively.…”

“…By carefully selecting the most appropriate methodology, some of the known limitations can be mitigated. One example is the application of time-lapse thermography, which allows to observe climatic and material transient changes over prolonged periods of time [5]. This in turn enables the observation of defect patterns over-time, allowing for enhanced interpretation.…”

Quasi-quantitative infrared thermographic detection of moisture variation in facades with adhered ceramic cladding using principal component analysis

“…For instance, Fox et al [9] studied on the time-lapse thermography, in other words taking various time-dependent thermograms of the object and evaluating the thermal response over time, through in situ inspections for the detection of building defects such as cracks. Theodorakeas et al [10] made a quantitative analysis of active IRT results through laboratory experiments and numerical simulations to detect plastered mosaics.…”