Bill Houghton, Sebastopol, CA
That's actually an unfair title, since I've yet to see any evidence that the person who worked on our house after World War II was a real carpenter; indeed, all the evidence has been that s/he had once seen a picture of a hammer before beginning work on the house. S/he did scrounge really, really well; we keep finding recycled this and that used in the construction work. But follow good building practices s/he did not.

We're now taking apart a room paneled entirely in knotty pine, except for some large (and air-leaky) windows, as part of an extensive reworking. The photo below is of a corner in the room, near the ceiling. The white spots in the very corner, at the top of the photo, are light shining through from the open space behind that corner. It would be a solid line of white, were it not for the cobwebs otherwise filling the space.

No wonder it was so hard to heat that room; I've found several of these gaps as I go around the room taking down the wood.