Lawrence Berkeley National Laboratory used infrared (IR) imaging as part of its field testing for ongoing research on the energy performance of window attachments. These three photos show the same window, with an interior low-e panel attached, under three different pressure conditions simulating windy weather. Even with a fairly tightly sealed interior window panel, the moderate wind level significantly increases air leakage. Note that each IR image encompasses the same temperature range—a critical detail when doing side-by-side comparisons.

Photo: Lawrence Berkeley National Laboratory