What is the FEMA 50% rule and how does it affect my Miami remodel?
Answered by AskBaily Editorial · Updated
Short answer
Under FEMA's Substantial Improvement rule, if cumulative renovation costs over any rolling period exceed 50% of the pre-improvement structure value, the entire structure must be brought up to current flood-code — finished floor elevation above BFE, breakaway walls, flood vents, flood-resistant materials below BFE. Miami-Dade enforces on the 5-year rolling window. This single rule has killed more Miami whole-home renovation budgets than any other.
In detail
Under FEMA's Substantial Improvement rule, if cumulative renovation costs over any rolling period exceed 50% of the pre-improvement structure value, the entire structure must be brought up to current flood-code — finished floor elevation above BFE, breakaway walls, flood vents, flood-resistant materials below BFE. Miami-Dade enforces on the 5-year rolling window. This single rule has killed more Miami whole-home renovation budgets than any other.
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