How often is the code updated?
Every 3 years.
Where does the code come from?
The Florida code is based on the International Building Code, or the "base code", and adapted for state-specific needs.
Can I read the code?
Yes. It is available here. You can even see previous versions at that site.
What requires a permit?
I talk about this all the time. Here's the official stance:
Any owner or authorized agent who intends to construct, enlarge, alter, repair, move, demolish, or change the occupancy of a building or structure, or to erect, install, enlarge, alter, repair, remove, convert or replace any impact resistant coverings, electrical, gas, mechanical or plumbing system, the installation of which is regulated by this code, or to cause any such work to be done, shall first make application to the building official and obtain the required permit.