I've referenced the floor load a few times. It's composed of its component parts — all of the sub-components of a building type. Here is how it works at a conceptual level.
Blended load factor: 0 sf/person
The pie chart shows the % occupancy contribution. Lower sf/person requires a higher overall floor load, especially if there is a lot of it. Since this isn't that intuitive, I will build a scenario explorer.