Common Area
There are two components of the term "common area". If referred to in association with the Rentable/Usable or Load Factor calculation, the common areas are those areas within a building that are available for common use by all tenants or groups of tenants and their invitees (e.g., lobbies, corridors, restrooms, etc.)
On the other hand, the cost of maintaining parking facilities, malls, sidewalks, landscaped areas, public toilets, truck and service facilities, and the like are included in the term "common area" when calculating the tenant's pro-rata share of building operating expenses.