Well, the exterior need not be wood - and in places like California wine country, should not be. A steel roof, concrete ("hardi") siding, and "WUI" vents with

Well, the exterior need not be wood - and in places like California wine country, should not be. A steel roof, concrete ("hardi") siding, and "WUI" vents with relatively fine pores, when employed properly, can make the building exterior quite fire resistant, regardless of the flammability of the interior framing. That being said, I do have steel sprinkler lines running onto the roof ...