These Thermal Images show the relative surface temperature. Blues and Purples are relatively cooler than the Oranges, Reds and Whites. The exact temperature is not really an issue here, the relative temperature is.
These two images demonstrate a significant heat loss. Basement wall insulation is not a standard for new homes in this area. A significant savings is available.
This Image is a door. First you notice the trim around the opening. Over the top of the door there is a classic thermal signature of air leakage. The relatively cooler air is being pulled across the drywall. It is described as a feather pattern. The relative temperature scale is there. Reds are relatively warmer than greens and blues re relatively cooler. You can also see the gap between the door and the frame. This looks like air moving. It isn’t. The technical term is boundary layer. It shows up in the IR image as relatively cooler because the air in the gap is still. You will see this in corners, and other recessed areas. The slot in a screw head is another.
One of my first new homes. 2:00 pm 37.85° N July, 19 2011, south elevation.. This cantilever bay is 2 feet deep. The lap siding is an 11 inch lap. Sightly more than 48 inches of shade. The space between the cantilevers is a 30 inch eve overhang. The 4 inch gutter is not installed yet. There is 96 inches+ of shade there. Surface temp difference, shade to no shade, is about 20° F.