The percentage difference between rentable and usable square feet.
Measurement · US, Global
The percentage difference between rentable and usable square feet.
Also called add-on factor or core factor. A 25% loss factor means the tenant pays rent on 25% more area than they can use. Loss factors vary materially: trophy Manhattan often runs 28-32%; modern London Class A around 12-15%; Singapore Grade A around 10-15%. A 5% difference in loss factor is real money.
A 30,000 RSF floor with 25% loss factor = 22,500 USF.
Loss factor is part of the measurement vocabulary that institutional Class A occupiers, landlords, and advisers use across US, Global markets. Understanding it correctly affects how you read lease documents, model occupancy economics, and benchmark deal terms across cities. Class A Atlas tracks regional variation alongside the global standard so cross-border occupiers can translate quickly.