The building efficiency ratio is a key metric in facility and real estate management, used to determine how efficiently a building's space is utilized. The IFMA Real Estate and Property Management competency defines the formula as:
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* Option B (Correct): This formula shows how much of the gross building area is rentable, making it a critical factor in leasing decisions.
* Option A (Common Area / Usable Area) does not measure building efficiency, but rather common area factor.
* Option C (Gross Area / Usable Area) is not a standard efficiency metric.
* Option D (Usable Area / Rentable Area) measures tenant efficiency but not building efficiency.
A higher efficiency ratio means less wasted space and more rentable revenue.