Q: What is the "50% Rule"?

The " 50% Rule " requires that if the cost of repair, reconstruction, rehabilitation, or addition equals or exceeds 50% of a building’s market value, the entire structure must comply with current floodplain requirements. Keep in mind that under the 50% Rule, repair, reconstruction, rehabilitation, or addition costs include permits pulled within the prior 12 months from the date of your most recent permit application. You will be required to complete a substantial damage worksheet along with your permit application.

Question 1

What is the "50% Rule"?

Accepted Answer

The "50% Rule" requires that if the cost of repair, reconstruction, rehabilitation, or addition equals or exceeds 50% of a building’s market value, the entire structure must comply with current floodplain requirements.

Keep in mind that under the 50% Rule, repair, reconstruction, rehabilitation, or addition costs include permits pulled within the prior 12 months from the date of your most recent permit application. You will be required to complete a substantial damage worksheet along with your permit application.

Question 2

How do I calculate market value for the 50% Rule?

Accepted Answer

To determine your home or structure’s market value, use either the Hillsborough County Property Appraiser market value determination or an appraisal by a state-licensed appraiser. The Hillsborough County Property Appraiser offers a 50% Rule improvement calculator online for assistance.

Question 3

Can I use the Hillsborough County Property Appraiser’s market value for my property to calculate the 50% Rule?

Accepted Answer

Yes. The Hillsborough County Property Appraiser offers an online 50% Rule improvement calculator to help.

Question 4

Can I hire a private appraiser instead of using County values?

Accepted Answer

Yes, private appraisers can provide an independent market value assessment.

Question 5

What is considered "substantial damage?”

Accepted Answer

Substantial damage occurs when the cost of repairs or improvements to a building equals or exceeds 50% of its market value, per FEMA's guidelines.

Question 6

What happens if my home or structure is considered substantially damaged?

Accepted Answer

If your home, or structure, is considered to need substantial improvement or to have substantial damage, consult with a design professional. The structure must be brought into compliance with current floodplain requirements.

Question 7

Do I need a permit for all repairs or just major ones?

Accepted Answer

Any rebuilding or structural repairs within a Special Flood Hazard Area require a permit to remain in compliance. Cosmetic repairs, including drywall removal or replacement, do not require a permit but require the Substantial Damage Packet to be submitted to the County for review. Please email the Substantial Damage Packet to permitting@hcfl.gov. Submit permit applications through HillsGovHub.

Question 8

How do I apply for a permit? What information do I need?

Accepted Answer

The permit process is managed through the Hillsborough County Development Services HillsGovHub portal. Here you can apply for a permit and upload all required documentation to meet permitting requirements.

Apply for a Residential Miscellaneous Permit, if you plan to return your home to the condition it was in prior to the hurricane
A Residential Alterations Permit would be applicable if you plan to raise your home or make significant, structural changes to the interior
If you plan to knock down your home or structure, apply for a Demolition Permit. For a list of demolition submission requirements, visit the residential demolition checklist.

Question 9

If I didn’t receive a mailer, does this mean that my damages are not considered substantial?

Accepted Answer

Not necessarily. It is the property owner’s responsibility to determine whether the repairs or reconstruction meet the 50% Rule threshold.

Question 10

What happens if I already started or have completed repairs?

Accepted Answer

If you have started or completed repairs without obtaining the necessary permits, you may still need to take action to comply with regulations. Completing repairs without a permit could result in fines or additional corrective actions to meet compliance standards. Consult a licensed contractor to evaluate your current repair work and ensure it aligns with FEMA and County regulations.

Question 11

When can I start repairs?

Accepted Answer

Repairs should begin after you have applied and been approved for a building permit through Hillsborough County Development Services.

Question 12

What if I can’t afford all the repairs?

Accepted Answer

When your home or structure has substantial damage and is subject to FEMA’s 50% Rule, there is much to consider. To bring your home or structure up to FEMA’s base flood elevation standards, your structure might need to be raised or rebuilt from the ground up. Contact Hillsborough County Development Services to begin the permitting process and find a local, trusted contractor to obtain an estimate. FEMA’s Substantial Damage Quick Guide provides a list to include when estimating repairs and improvements.

If you have a current flood insurance policy, you may be eligible for FEMA’s Increased Cost of Compliance coverage (ICC). Policy holders may receive financial assistance to help offset costs to bring their structure into compliance with the local floodplain management ordinance. Visit FEMA’s ICC webpage for details.

Question 13

Why Does Compliance to the FEMA 50% Rule matter?

Accepted Answer

Compliance ensures your property remains eligible for the National Flood Insurance Program (NFIP) and avoids penalties. The County’s participation in the Community Rating System helps reduce flood insurance premiums and ensures compliance with FEMA floodplain regulations.

Flood prone communities who do not comply with the FEMA 50% Rule may be suspended from the NFIP. If suspended, Hillsborough could incur penalties such as:

No resident will be able to purchase a flood insurance policy
Existing flood insurance policies will not be renewed
No Federal grants or loans for development may be made in identified flood hazard areas under programs administered by Federal agencies such as HUD, EPA, and SBA.

For additional information on the importance of the NFIP and its sanctions and requirements, visit the FEMA NFIP page.

Question 14

What is Hillsborough County's role in floodplain management?

Accepted Answer

The County participates in the NFIP and the Community Rating System, which helps reduce flood insurance premiums for residents. To maintain compliance, the County enforces regulations through its Floodplain Management Ordinance, as outlined in Chapter 8 of the Hillsborough County Construction Code. Flood damage control regulations can also be found in Part 3.06.00 of the Hillsborough County Land Development Code and general submission requirements for all construction within the Special Flood Hazard Area (SFHA) can be found here. Hillsborough County enforces local, FEMA, and State of Florida building code requirements.

Question 15

What resources are available?

Accepted Answer

Contact Hillsborough County Development Services at permitting@HCFL.gov
Substantial Damage guidance, definitions, and cost estimation tools
Special Flood Hazard Area requirements
Substantial Damage/Improvement packet (PDF)
FEMA’s 50% Rule explained
Tips to rebuild after the storm

Rebuilding & Repair - Hurricane Milton Recovery

Resources for homeowners who need repairs due to damage from Hurricanes Helene or Milton

A. FEMA's 50% Rule

After the review, does your home or structure meet the Substantial Damage criteria?

B. Disaster Declaration Expedited Permitting

C. Required Electrical Inspections for Residents Who Experienced Flooding

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