Final answer:
Different occupancies typically require a rated wall for separation according to building codes to ensure safety and comply with regulations.
Step-by-step explanation:
When two different occupancies exist in the same building, they often must be separated by a rated wall. This requirement is in place to ensure safety and comply with building codes, which dictate the type of occupancy separations needed based on factors like fire risk and occupancy type. For instance, a residential area might need to be separated from commercial space to prevent the spread of fire and allow for safe evacuation paths. The exact requirements for a rated wall, such as its fire-resistance rating, will depend on the specific building code that applies to the location of the building, such as the International Building Code (IBC) or other local regulations.