Which method utilizes temperature differences to identify air leakage areas?

The method that utilizes temperature differences to identify air leakage areas is thermography. This technique employs infrared imaging to detect variations in temperature on surfaces, which can indicate the presence of air leaks. When there is a significant temperature difference between the indoors and outdoors, the infrared camera can highlight areas where conditioned air is escaping or unconditioned air is infiltrating.

For example, if a building is heated in the winter and the outside temperatures are much colder, thermography can reveal cooler spots on the interior surface of walls, windows, or ceilings. These cooler areas may correspond to locations where air is leaking, enabling practitioners to make precise assessments of air barrier performance.

In contrast, other methods listed, such as the smoke puffer and blower door test, operate through different principles. The smoke puffer visually demonstrates airflow patterns by releasing smoke near suspect areas, but it does not use temperature differences for detection. The blower door test measures the overall air tightness of a building by creating a pressure differential but does not specifically identify leakage areas based on thermal variations. A manometer is used to measure pressure differences but does not directly identify air leakage through visual means or thermal imaging.