Here in the Czech Republic, before you start moving to other places, you need to put everything on the paper. Make all documentation about how it will be, detail drawing, waste documentation, etc. Than all departments like fire, building, health departments and others will need to make approval based on that documentation. Than you make all the changes in your new facility. After all is done, all departments will come for an inspection and they will give you an approval for roasting facility. If it is the same in the USA I would probably go check with all the departments about their requirements. That is because some requirements are hard to provide in some general building! Also they should guide you what to do. Do not forget to check if there is requirement for microclimate for storing the coffee.
Just wondering it is the same in the USA? What you need to have or do, to build the roasting facility?