We are working with a tenant that is occupying a full floor. To the best of my knowledge, so long as all areas of the floor have access to both rated stairwells, then a common corridor in not required. In addition, there is a card access system in place which only allows the elevator to open on that particular floor to access card carrying people. Therefore, the tenant could literally get off the elevator directly into their space without any corridors. The tenant however, has requested that a corridor be put in for their own security purposes. Since the corridor is not required by Code, is it usable space or would it be considered floor common? Either way they pick it up, however, if their requirement calls for 'X' number of usable square feet, we think that corridor is actually usable space since it is not a code requirement but merely are tenant specific requirement. Please advise.