Debate is now in progress regarding AFCI in basement 'finishing' jobs. It is under the NJ UCC Rehab, and a recent opinion from State DCA says... 'Yes, AFCI unless you are extending an existing circuit' Rehab is based on the 2008 NEC now, and AFCI is required.
The debate is what section of the Rehab Code applies to finishing an existing basement, with no increase in structural volume.
This is the New Jersey take, other states will vary
