Every lot shall have an area of not less than seven thousand square feet per family; except that, if a lot has less area than required in this chapter and was a lot of record prior to February 12, 1971, the effective date of the ordinance codified in this section, such lot may be used for one single-family dwelling, provided that all other district regulations are observed. (Ord. 520 (part), 2014; Ord. 344 (part), 1987: prior code § 11-3-1 (c) (4))