Efficiency of the usable area to meet tenant’s requirements. Efficiency of usable area is dictated by such factors as: building shape, core location, column size location, floor size, leasing depth, corridors, etc.
That percentage of the building which is common area, allocated to the tenants to increase their usable area to rentable area.
The rentable area includes the usable area plus a pro rata share of common areas on the entire office floor and in the building itself (e.g. main lobby) excluding vertical shafts, such as elevators, stairs, mechanical risers, etc.
Office area actually occupied by a tenant for its sole and exclusive use.