lumber

We've designed the house to avoid using softwood lumber as much as possible. This is the kind of wood that's typically used for framing (as 2x4s and 2x6s) or furring (the thin pieces of wood used to attach gypsum drywall to concrete block walls) in conventional construction. The two major problems with using softwood lumber in Miami are termites and mold.

However, it turns out we need to use a few 2x4s in the house...

We're using wood around the door frames in the interior walls (but not in the exterior walls). The 2x4s are going to give the partitions a little extra stiffness so that they don't rattle when we open and close the doors. The doors are far enough from the edge of the foundation that the wood shouldn't attract termites (which couldn't cause structural damage to the house even if they did find their way inside).

From a sustainability standpoint, dimensional lumber like this is fine to use, as long as it is not pressure treated (which, unfortunately, is common in Miami because of the termite and mold problems). Since the wood is harvested in the United States and is not a tropical hardwood, it does not need Forest Stewardship Council certification to be used in LEED for Homes construction without a penalty.