Rated Structure to Support 1/2-hr Rated Barriers?

The International Building Code Section 707.5.1 (2015 Edition) requires structure to have at least the level of fire resistance as the element it is supporting:

707.5.1 Supporting construction. The supporting construction for a fire barrier shall be protected to afford the required fire-resistance rating of the fire barrier supported. Hollow vertical spaces within a fire barrier shall be fireblocked in accordance with Section 718.2 at every floor level.

   Exceptions:

1. The maximum required fire-resistance rating for assemblies supporting fire barriers separating tank storage as provided for in Section 415.9.1.2 shall be 2 hours, but not less than required by Table 601 for the building construction type.

2. Supporting construction for 1-hour fire barriers required by Table 509 in buildings of Type IIB, IIIB and VB construction is not required to be fire-resistance rated unless required by other sections of this code.

The project is a three-story hotel and each unit is required to have a 1/2-hour fire resistance rating between units and between the unit and the corridor. 

Is the building structure required to have at least a 1/2-hour rating on account of these separations?

I see two potential outs that would not require it - first being that the 1/2-hour fire resistance rating could be considered a "fire partition" and not a "fire barrier". Second out is exception #2 listed above although it speaks to a 1-hour rated fire barrier and not a 1/2-hour fire barrier.

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