Occupancy and Change of Use
Occupancy rules govern when a building or part may be used for its intended purpose, and change-of-use rules address converting a building to a different major occupancy. Candidates must know that occupancy requires the CBO's authorization where the Code requires it, that it follows completion of required inspections, and that a change of use may trigger upgrade requirements even without construction. A common trap is assuming that a change of use with no physical work needs no permit - it often does, and the Code may require the building to meet standards applicable to the new use.
Another trap is conflating occupancy with permit issuance: a building permit authorizes construction, not occupancy. Partial occupancy may be permitted for a portion of a building if the CBO is satisfied that the portion is safe and compliant. Questions often present a tenant moving into a shell space before inspection; the correct answer is that occupancy without authorization is non-compliant and may ground an order.
Candidates should understand the analysis for change of use: identify the old and new major occupancies, assess whether the new use triggers higher fire safety or egress requirements, and determine whether compensating measures or upgrades are needed. The CBO may impose conditions and may require a permit application for the change.
Rule of thumb: permit is to build, occupancy is to use, and change of use is a compliance event even with no hammer swinging.
Worked example: a warehouse is converted to a retail store with only cosmetic work. The change of use may require the building to meet requirements for the new occupancy (egress, fire separations, sprinklers), and a permit and occupancy authorization are likely required.