I build huge crates to ship freight elevator doors in (occasionally do work on them also). We're the largest freight elevator door company in the world, we have doors in every military or government building that needs them in the US (including the pentagon [i remember doing a repair for that job a few years ago]) white house, military bases, new WTC, airports, post offices, all the way down to walmarts and grocery stores.
We also do work world wide, the United Arab Eremites seems to like building new building and buying our doors. Also places like Petronas Towers and thousands of building throughout the world.
Theres usually 2 parts to a door, right now we have a job that one piece weighs 1250lbs. All doors are fire rated to I believe 1.5 hours at least (should see them be tested, these thousand pound doors warping, twisting and melting in an extreme heat oven
I go through litterally tonnes of wood a week, sadly, it is all economy crap, I think one day if I happen to stumble across a long piece with straight grain I'll see if I can't make a bow out of it, Most likely will end in failure, but fun none the less!