Basement height for restaurant/ Chicago Building Code

[Inspector C]

This is an esoteric code question for Chicagoans and our lovely building code--

Trying to determine the minimum ceiling height for a basement for an existing building.
Occupancy type is a restaurant < 100 people, so its Mercantile (not Assembly).

In the CBC in Group 3, there are a bunch of special requirements by Occupancy and some (but not all) of these Occupancy types have a "Ceiling Heights" subsection that describes the ceiling heights for that occupancy type. Mercantile (or Assembly) is not one of them. The Existing Buildings section does not elaborate on this, either. Am I missing something?

Thanks.

[Markus Keller]

A restaurant is considered a Class C assembly unit.
Your question cannot be fully answered as stated because you have not defined what the basement will be used for. Ceiling height will vary depending on use and use will be determined by DCAP based on your architectural plans and allowed or disallowed depending on conditions.
Ceiling height is one question and then percentage of non-compliant height is another question (soffits, pipes, ducts)
Also see 3(13-84-331)

[Inspector C]

Thanks for the response. Your general comment that it is somewhat TBD by DCAP is probably the most important thing.

Good point about the use (in this case its a commercial kitchen in the basement).

Thanks for the 13-84-331 that is an important consideration re. sprinklers for Assembly.

Interesting that it would be considered Assembly, I thought that since this restaurant is less than 100 occupancy it would be Mercantile, per 13-56-090, Exception (a) ("Restaurants, bars, taverns and similar occupancies having a capacity of not more than 100 persons shall be classified as Class F, mercantile units.")

[PHILE Riwen]

Thanks for sharing this information.