(1) For purposes of this section, the term:
(a) “Cumulative substantial improvement period” means the period during which an aggregate of improvements or repairs are considered for purposes of determining substantial improvement as defined in s. 161.54(12).
(b) “Local government” has the same meaning as in s. 163.2514.
(2) A local government that is participating in the National Flood Insurance Program may not adopt or enforce an ordinance for substantial improvements or repairs to a structure which includes a cumulative substantial improvement period.