Underneath its skin: Pugsley re-siding in 1963

I'm working on my first siding project, a very small repair of one tiny corner of the house. And in trying to understand the construction, I went digging around in photos the former owners left. These photos below are a little grainy, because I am working from xeroxed copies, but they're still very interesting. These are photos from June of 1963 (the month I was born), when the house was last sided. 

The photos illustrate two important factors of the older construction methods used on this house.

First, the house has a kind of "skip-sheathing" underneath the cedar shingle siding -- little strips of 1x2 furring or nailers in horizontal lines, that the shingle siding is nailed to. Here are two photos of the back of the house, showing the skip-sheathing clearly.

This creates an airspace between the lathe and plaster wall and the shingle siding, which lets the house breathe. I think it is an important component of the longevity of this house. Here is an article that explains, in somewhat more technical terms, why.

Two, in places the house has two layers of siding. Here below, you can see the new siding being nailed on top the old. 

The house is unusually airtight and energy efficient for an old house, and I think both of these things contribute to it, as well as the thick plaster walls, the 1830's window construction made without pulleys and ropes, and the storm windows on top of that. 

We had an energy assessment the first winter we were in the house--one of those free ones that companies offer, to sell you things like blown-in insulation, re-siding and replacement windows--, and the guy kept wandering about all confused because he couldn't find any major temperature variations at the window trim or electrical outlets. All houses have little draughts, he kept saying. Ours doesn't. He couldn't find anything to suggest, not even window replacement.

And yet, there is no foam insulation or wrapper, nothing "artificial". No modern materials. I'm not one to valorize older materials simply because they're older, but I do feel that old house building methods have stood the test of time, are proven to last and are worth taking the time to understand and replicate when repairing an old house.