[Cob] green treated wood

[Mary Lou McFarland]

I like to keep my ear to the ground on all kinds of building products and 
processes and I caught a spot on This Old House the other night about green 
treated lumber.  Apparently the last two years green treated lumber hasn't 
been processed with the copper/arsenic stuff.  Now it is some other copper 
based stuff that is suppose to be less toxic.  One pitfall of this new 
product is that it creates a chemical reaction with GALVINIZED metal.  so if 
using this product with metal hangers, use stainless steel hangers and also 
stainless steel nails.  If you have to use galvinized product then wrap the 
end of the green treated board with a vapor barrior but you'll probably 
still need to use the stainless steel nails.  If needing a lag bolt the bolt 
was run through a short length of plastic tubing.
I know sometimes we have to incorporate readily available products whether 
it's our ideal or not, so thought this might be a good heads up