My above question is not for a particular region, it is general in the real estate industry. Thanks
A “loss factor” is the product of multi-tenanted buildings and depends entirely on how much common space (stairwells for example) is shared and how many tenants are sharing it.
In reality, a loss factor is usually determined by how much a landlord can get away with, not by actual measurements or calculations. This is known as “grossing-up” the rentable area of a space.