I inspected a house yesterday that was built of ammo boxes. Stucco on the exterior, drywall on the interior. They apparently filled them with sawdust for insulation (yikes!). Among numerous other problems, there was quite a bit of termite frass around. I wonder if fuming would even help? I guess it depends on how well the boxes are sealed.
The picture is from the garage, the only room without drywall (go figure).
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