[Greenbuilding] recycled wood (was Glass ceiling)

[Chris Koehn]

Chiming in on this, as I've worked with thousands of board feet of recycled timber.

In my experience it is imperative to know where your wood comes from, for lots of reasons, including possible contamination. While most factory timber has at most surface contamination (often lead paint) it can also have hidden damage from other sources, including forced air heating, which tends make old growth fir and yellow pine timber brittle, especially on the ends.  
I got a chance to work on the Kinsol Trestle a few years ago: a very large wooden railway bridge here, that was recently refurbished for use as a pedestrian  bridge. Making the main span across the Koksilah River is a series of Howe trusses, original to the trestle and dating from the early 1900's. They have been soaked repeatedly with all sorts of nasty preservatives, which worked splendidly, but completely contaminated the timber- so much so we had to take great precautions working with it. This wood will never be useful in any other capacity, it is contaminated to the core. 
Salvaged barn timber, of which there was seemingly endless supply in the upper mid-west, is very difficult to grade for re-use as structural members. 
A case can be made (and has been made) that the best and highest use for high grade salvaged timber is as re-sawn non-structural boards or veneers, celebrating it's beauty rather than it's strength.
Having said that, the Long Bell Mill in Washington supplied the entire timber framing industry with old growth, high grade reclaimed fir for half a decade in the '90's. The buildings that were constructed from this wood, if cared for properly, will last for centuries.

re: shingle style glass: we have built a 1/2" space between layers, with a 2" overlap, facilitating cleaning. Since this is a covered entry, we don't mind if the occasional wind-driven rain makes it's way through the gap.

Chris Koehn
TimberGuides
Vancouver Island