Above the Surge

Storm Surge Elevation Requirements for Monroe County Construction

In the Florida Keys, building height is not about views. It is about survival. Learn how high your building needs to be to stay above deadly storm surge waters.

Feet Average BFE

15+

Feet Cat 5 Surge

60%

Insurance Savings

Watch the Water Rise

See how storm surge affects buildings at different elevations. Move the slider or pick a storm category.

BFE: 11 ft

0 ft

Storm Surge Height

Storm Surge Height:

0 ft

Building First Floor:

12 ft

Monroe County Flood Zones

Different zones have different requirements. Know your zone before you build.

Coastal High Hazard

Highest Risk

VE zones face wave action on top of flooding. Most oceanfront Keys properties fall in this zone. BFE typically 10-14 feet.

Bottom of lowest floor at or above BFE
Breakaway walls required below BFE
Pilings or columns required
No enclosures below BFE

100-Year Flood Plain

High Risk

AE zones flood without wave action. Interior Keys properties often fall here. BFE shown on flood maps.

Top of floor at or above BFE
Flood vents required in foundation
Fill or elevation allowed
No mechanical below BFE

100-Year (No BFE)

High Risk

A zones are flood prone but FEMA has not determined exact BFE. Requires engineering study to establish elevation.

Engineer must determine BFE
2 ft above highest adjacent grade
Similar rules to AE zones
May require Letter of Map Amendment

Minimal Flood Risk

Lower Risk

X zones are outside the 100-year flood plain. Rare in Monroe County, but some elevated areas qualify.

No federal elevation requirement
Local codes may still apply
Flood insurance optional but recommended
Still at risk from major hurricanes

Insurance Cost by Elevation

Building higher saves thousands in annual flood insurance premiums.

2 ft Below BFE

$8,500/yr

High Risk Premium

At BFE

$3,200/yr

Standard Premium

3 ft Above BFE

$1,400/yr

Preferred Rate

Building 3 feet above BFE can save over $7,000 per year in flood insurance.

Common Questions

Base Flood Elevation is the height water is expected to reach during a 100-year flood event. In Monroe County, BFE ranges from 7 to 14 feet depending on location. Your building's first floor must be at or above BFE.

Monroe County requires buildings in V zones to have the lowest horizontal structural member at or above BFE. Many areas require freeboard of 1-3 feet above BFE. Key West requires 1 foot of freeboard.

Buildings below required elevation face much higher flood insurance premiums, sometimes 10x or more. They also require expensive retrofits or may be denied permits for renovation. Non-compliant buildings can lose insurance availability entirely.

Look up your property on FEMA's Flood Map Service Center or contact Monroe County Building Department. Your FIRM (Flood Insurance Rate Map) panel shows BFE for your specific location. An elevation certificate may be needed for exact measurements.