When two (2) or more non-residential uses in the same use category share a building or structure, all of the uses in the same use category shall be added together to derive the total gross floor area, to determine the required number of berths and spaces for that use category.
When two (2) or more uses in different use categories share a building or structure, the building or structure is only required to provide enough berths and spaces to meet the requirement for the use category with the highest requirement, and not the combination of requirements for all use categories provided that all uses that require loading have access to the loading area.
At least one (1) loading berth shall be provided when the sum of the gross floor area of the separate uses exceeds the minimum gross floor area requiring loading berths for any one of the separate uses.
For purposes of calculating loading requirements for non-residential uses:
D.C. Mun. Regs. tit. 11, r. 11-C902