Roofs get wet at night
Heat flows through the easy path
Framing is a bridge.
You can see that the dry areas of the roof are where the heat can leak out.
It appears that there is a flat ceiling in this house above sloped sides, because there is a dry area between the upper and lower wet areas—heat is leaking out of the framing joints where insulation is discontinuous.
It also looks like there is a stairway at the front door, because the wet shingles extend all the way, unimpeded. The insulation is continuous.
Wood is not a good insulator (unless we're talking about electrical insulation).