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Infrared thermography is a quick, nondestructive way to identify building issues such as: insufficient insulation, wasted heating and cooling energy, water damage due to plumbing leaks, electrical hot spots, and structural problems. The process can be applied to industrial, commercial, and residential buildings alike. The images provide a survey of temperature information over a large area exposing spatial variation which single point thermometers cannot replicate. Images can also be taken at a distance from hard to reach or dangerous locations. This information can help suggest retrofits to improve energy efficiency and identify structural problems before they become apparent visually.

A trained inspector will survey both the interior and exterior of the building to identify areas of strong temperature contrast which might suggest heat loss to the outside during winter or heat gain from the outside during summer. Findings must be followed up with careful analysis of the imaging conditions, material properties such as emissivity and thermal conductance, and a structural analysis of the heat flow in the building. The quality of a thermographic analysis depends primarily on the accurate interpretation of thermal images by a trained inspector as well as the technical capabilities of the camera. Here are some common issues which must be considered when interpreting thermal images:


 * Some materials do not effectively radiate infrared light (low emissivity) leading to artificially low temperature readings.
 * Surface temperatures can be affected by evaporative cooling of damp materials.   This evaporative cooling can help    identify leaks and water damage, but it can also lead to faulty     conclusions about the insulating properties of the envelope.
 * Wind conditions during outdoor measurements can greatly affect the surface temperature due to convective cooling.
 * Metals reflect infrared radiation; this can lead to low temperature objects seeming to be hot due to the reflection of a nearby    hot surface
 * Each building will have unique energy use characteristics and requirements.   This makes identifying    appropriate improvements difficult, particularly since retrofits may be     costly with long payback times.
 * Surface temperature variations can be fairly small and since the imaging color scale is based on the minimum and maximum    temperature a small variation may be “washed out” by a nearby high     temperature feature leading to “thermal blindness”
 * High humidity levels in the air can reduce evaporative cooling making measurements from day to day inconsistent.
 * Materials take time to absorb and distribute heat.   Sudden changes in conditions such as sunrise/sunset, weather     changes, or internal heating and cooling cycles can lead to inaccurate     modeling and conclusions.   Buildings should ideally maintain a     stable temperature conditions for 12 hours prior to a thermographic evaluation.

These issues highlight the need for well-trained inspectors in order to produce reliable evaluations. Some of these issues can be leveraged in the investigators favor though. Manipulating air flow currents can exaggerate or diminish evaporative cooling and control the contrast of wet or damp areas. Adding heat to a system with a heater can reveal variations in insulation as more thermally conductive materials will dissipate the added heat faster and produce valuable contrast in thermographic images.

''Kylili, Angeliki; Fokaides, Paris A.; Christou, Petros; Kalogirou, Soteris A. (2014-12-01). "Infrared thermography (IRT) applications for building diagnostics: A review". Applied Energy. 134: 531–549. doi:10.1016/j.apenergy.2014.08.005. ISSN 0306-2619''

''Dall'O, Giuliano; Sarto, Luca; Panza, Angela. "Infrared Screening of Residential Buildings for Energy Audit Purposes: Results of a Field Test". Energies. 6 (8): 3859–3878. doi:10.3390/en6083859.''

InterNACHI® - Int'l Association of Certified Home Inspectors". www.nachi.org. Retrieved 2020-11-17.

''"The Use of Thermal Infrared Thermography In Building Inspection". A+ Inspections. 2014-12-10. Retrieved 2020-11-17.''