Yes, also code section 305.1 exception 1, even 50 percent of the floor area at 7 feet and no other portion of the required area may have a ceiling height of less than 5 feet.
and 310.1 shall have a egress.
and 314.3 shall have a smoke alarm.
To my understanding, it is up to the home owner weather they use this area as storage or habitable space, the code is requiring these measures be placed because the space meets the use of habitable space and it could be used in the future. The code is not stating that this area has to be finish, just the safety aspects be in placed.
Mark Bolt