Haiku: Thermal Bridging

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).