“Residential single-unit” means all dwelling units occupied by one family or by not more than five unrelated persons, including, but not limited to, detached single-family residences, and zero lot line buildings wherein the building is on a separate fee simple lot, used for residential purposes, and is served by a separate water meter. (Ord. 3024 § 1, 2013; Ord. 2529 § 1, 2004; Ord. 2069 § 2, 1996; Ord. 416 § 1.10, 1968)