USF, stands for Usable Square Feet, and RSF stands for Rentable Square Feet.
This is extremely important specifically in the office building setting.
For example, the office I’m walking in is roughly about 2,300 square feet give or take that is rentable square feet.
The usable square feet is much less than that.
The difference is the core factor.
The core factor of each building varies, and it depends on what amenities the building has.
So for example, the more amenities the building has, the higher the core factor is going to be.
Such as common areas, such as the restrooms, the hallways, if the building has a common conference room, if the building has a fitness center, and rooftop.
The more common areas the building has, the higher the core factor is going to be.
So this space is 2,300 square feet of rentable square feet.
Let’s say the core factor is for example 20%.
20% is 460 square feet of the 2,300 square feet is the core factor.
We would subtract that 460 square feet from the 2,300 square foot space we’re standing in now.
That will give us a total of usable square feet of 1,840 square feet.
For this space, if the core factor is 20%, and the core factor can vary again.
Most of the core factors are in the teens to over 20%.
In this situation, if the core factor is 20%.
The usable square feet is 1,840 square feet, and the rentable is 2,300 square feet.
I hope this better explains the difference between usable and rentable square feet.