I see what you are saying a number of "national" building codes exist. I imagine in one sense these codes open up one's products to national markets when demons

I see what you are saying a number of "national" building codes exist. I imagine in one sense these codes open up one's products to national markets when demonstrated to be compliant. On the other hand they can also be used as alignment tools to see measure compliance of various markets. I have noticed a number of modular and manufactured builders will now build to any code standard.