Building Requirements

References to changes to the Flood Provisions

Summary of Most Significant FLOOD PROVISION Changes from the 5th Ed. FBC

1. Coastal A Zone and Limit of Moderate Wave Action: New definitions: CAZ delineated by LiMWA if on FIRM or if designated by the community. Requires buildings in CAZ to be designed according to Zone V requirements with two exceptions: backfilled stemwalls and dry floodproofing (nonresidential only), if designed to account for wave loads, scour, and erosion.2. FBC, Building requires buildings in SFHA to be designated by Flood Design Class, per ASCE 24.

3. ASCE 24 updated to the 2014 edition.

4. FBC, Residential modified consistent with ASCE 24-14:

Requires minimum elevation of lowest floor (Zone A) or bottom of the lowest horizontal structural member of the lowest floor (Zone V and CAZ) is BFE + 1 foot.

Clarifies flood provisions apply to substantial improvement and repair of substantial damage and if dwelling in more than one flood zone, the more restrictive requirements apply.

Specifies the determination of the net open area of flood openings and separates installation requirements into the new subsection.

Requires all walls to have flood openings, including breakaway walls.

Requires dwellings in Zone V and CAZ to have an exterior door at the top of stairs that provide access to the dwelling and that are enclosed by walls.

Adds requirements for tanks.

Reporting of Illegal Development

If you see illegal development in the floodplains, report it through our Request Tracker

Building Requirements

Reduce or avoid flood losses by building above the Base Flood Elevation. 

What is Base Flood Elevation?

The Base Flood Elevation (BFE) is the elevation that floodwater is anticipated to rise during the base flood. BFEs are shown on Flood Insurance Rate Maps and on the flood profiles. The BFE is the regulatory requirement for the elevation of structures. The relationship between the BFE and a structure’s elevation determines the flood insurance premium.

An elevation certificate is based on the property’s lowest floor. FEMA: Elevation Certificate

Structures Below Base Flood Elevation

Monroe County enforces the Monroe County Land Development Code Chapter 122 - Floodplain Management code. Structures built after December 31, 1974, must have the lowest floor elevated to or above the base flood elevation. The owner or purchaser of a structure with habitable space below the base flood elevation may be faced with significant unforeseen expenses.

Legally permitted enclosures below the base flood elevation are for building access, limited storage, and parking only. Limited storage means storage of lawnmowers, rakes, wheelbarrows, and similar pieces of equipment that are normally stored outside. Limited storage does not apply to household furnishings, workbenches, freezers, refrigerators, or other items subject to damage if exposed to saltwater. If you are purchasing a home with a finished enclosure below the base flood elevation, it may not be permitted construction and may be subject to enforcement proceedings.