Incidental Use Shall not Occupy more than 10%.... On a story that is part parking garage?

[akelly]

509.3 Area Limitations - The aggregate floor area of incidental uses shall not occupy more than 10% of the building area of the story in which they are located".

So this is easy to interpret if its say a building floor of about 30,000 square feet and you have a 2,000sf multi-purpose room loading as assembly. That room is under 10% of the overall "story" space so although I need to ramp up the exiting with panic hardware I will NOT need to rate the room and all hallways out. But how does this work if 20,000sf of that story is parking garage? And its separated by a 2 hour wall with no doors or exiting from the office space to the garage? Its all on the same floor and part of the same building so per the above code reference it would seem that's acceptable. BUT am I missing an exception in the code that would identify this parking garage as a completely separate entity in which case I only have 10,000sf of office space to calculate my 10% from?

Thanks in advance for everyone's help and comments on this. It is MUCH APPRECIATED

 

[mtlogcabin]

Accessory to the main occupancy which in this case is the parking garage
If the two hour separation is a fire wall not a fire barrier then you have 2 separate buildings of which you can take the accessory limits and apply them individually to each occupancy.
The building should be sprinkled so I don't see where anything needs to be rated