Zone AH — Shallow Flooding
Overview
Building Requirements
Structures must be elevated to or above the BFE. Adequate drainage paths required around structures to guide floodwaters. Flood-resistant materials required below BFE.
Key Facts
- Characterized by shallow flooding with ponding
- Average flood depths of 1 to 3 feet
- BFE is determined and shown on FIRM
- Mandatory flood insurance with federally backed mortgages
Who This Affects
Homeowners
Properties in Zone AH must carry flood insurance if you have a federally backed mortgage.
Check your propertyLenders
Lenders must ensure borrowers in Zone AH maintain flood insurance for the life of the loan.
Explore the APIBuyers & Sellers
Flood zone status affects insurance costs and property value. Get a certificate during due diligence.
View pricingCommon Questions
Why is flood insurance required in Zone AH?
Properties in Zone AH are classified as Special Flood Hazard Areas (SFHAs) by FEMA. Federal law requires flood insurance for properties in SFHAs that have mortgages from federally regulated or insured lenders.
How is Zone AH determined?
FEMA determines flood zones through Flood Insurance Studies that analyze local hydrology, topography, and historical flood data to produce Flood Insurance Rate Maps (FIRMs). Zone AH designations are based on the probability of flooding in any given year.
Can my property be reclassified out of Zone AH?
Yes. You can apply for a Letter of Map Amendment (LOMA) through FEMA if you believe your property is incorrectly mapped. This requires a licensed surveyor to certify that your property's lowest adjacent grade is above the Base Flood Elevation.
How do I verify my property's flood zone?
Get a flood certificate — an official document that identifies your property's flood zone based on FEMA's current maps. FloodCert provides instant certificates for any U.S. property.