A thermal x-ray uses an infrared camera that senses radiative surface temperatures rather than visible light. As a result, it takes photographs or videos that expose surface temperature anomalies. When looking at an infrared image, darker areas are cooler and lighter areas are warmer. For example, in an exterior image of a wall on a cold day, areas with inadequate insulation, significant air leakage, thermal bridging, or inefficient windows would appear with light colors exposing significant thermal losses. Additionally, moisture problems would reveal themselves with a distinctive ‘drool pattern’ and color variation. Thus, thermal x-ray diagnostics are very useful for finding thermal, air leakage, and moisture problems.