The minimum yards, parking spaces and open spaces, including lot area per family, required by this Zoning Code for each and every building existing at the time of passage of this Zoning Code or for any building hereafter erected, shall not be encroached upon or considered as part of the yard or parking space or open space required for any other building, nor shall any lot area be reduced below the requirements of this Zoning Code for the district in which the lot is located.
(1980 Code 153.07)