Is only one Light Probe Group enough for a building with several floors and room?

My scene was a building with 3 floors and many rooms, I am wandering if only one light probe group could cover all the rooms ,or it is necessary to create several ones for each floor or room?

 

I don't think how many groups it is matters, it's an organisation thing more than anything else. It's the amount of light probes that matters.

 

The probes should create volumes were your dynamic objects can move through it doesn't look like optimal volumes to me in your picture but it's hard to tell