Thanks very much for your comments and question!

The tower houses the stair and a small residential elevator, both of which rise from the ground floor up to a top-floor office and roof deck. The material is clear-finished cedar siding at the upper level, which then wraps around the back of that level so that when you're on the roof deck, you're sitting between the natural wood of the house and the trees beyond.

Those random-width cedar boards, as with the other siding, are milled from reclaimed lumber, provided by Armster Reclaimed Lumber in Guilford, Connecticut. Originally harvested in the 1940's and used in enormous juice tanks in Pennsylvania, the salvaged cedar from that era is a higher quality than new wood, and is also, of course, a sustainable product. (The other siding had first been used for bleacher seats in mid-century high school gymnasiums and for vinegar storage tanks!)

You didn't ask, but the red color of the random-width board and batten cladding was inspired by the Falun Red color found on vernacular structures throughout Sweden, from where the wife's family comes.