It shall be unlawful for any person to do, cause, permit, aid, abet or furnish equipment or labor to construct, enlarge, or modify a building or otherwise make a new use of a building for a second or additional dwelling unit on a single parcel of land within any zone district unless a Development Permit has been obtained and is in effect which authorizes such a second or additional dwelling unit. (Ord. 3451-A, 8/23/83; Ord. 4761 § 11, 5/18/04)