Here's information YOU need to know about the "50% Rule"

(also known as SI/SD - Substantial Improvement, Substantial Damage)

FEMA's Substantial Improvement/Damage

Building Valuation Calculation Table

Find an Elevation Certificate (If on Record)

Detailed Cost Breakdown Package

If your home or business is in the Special Flood Hazard Area (SFHA) and is not flood compliant (i.e. structure is below Freeboard, which is FEMA BFE + 1 foot), Unincorporated Lee County has flood damage prevention regulations that may affect how you remodel, renovate, or add on to your building.

The NFIP (National Flood Insurance Program) requires that any structure located in the SFHA (flood zones beginning with A and V) where the cost of proposed improvements or repairs equals or exceeds 50% of the value of the structure must be brought into full compliance with current flood damage prevention regulations.

These laws are required by the NFIP to protect lives and investment from future flood damages. Our community must enforce these laws in order for federally-backed flood insurance to be made available to Unincorporated Lee County residents and property owners.  Unincorporated Lee County, following the NFIP requirements, has the responsibility to determine "substantial damage" and "substantial improvement," and has implemented the procedures to do so. (Historic structures may be exempt from these requirements if the compliance would threaten the structure’s continued eligibility for historic designation).

SUBSTANTIAL DAMAGE definition: means damage of any origin sustained by a structure whereby the cost of restoring the structure to its ‘before damage’ condition would equal or exceed 50% of the market value of the structure. (Note: The cost of the repairs must include all costs necessary to fully repair the structure to its “before damage” condition.)

SUBSTANTIAL IMPROVEMENT definition: means any reconstruction, rehabilitation, addition, or other improvement of a structure, the cost of which equals or exceeds 50% of the market value of the structure (before any improvements are performed).

Base Flood Elevation (BFE) Definition

The predicted level of flooding measured from mean sea level. The elevation that water is anticipated to rise to in the event of a 1% annual chance flood (aka “Base Flood”). Since this is the elevation water is expected to rise to, the first livable floor should exceed BFE in order to avoid damaging effects from flooding. Base Flood Elevations are shown on Flood Insurance Rate Maps (FIRMs). This required elevation information is vital for new construction and some remodeling and renovation projects. Also, for flood insurance purposes, the relationship between the BFE and the structure's actual elevation (among other things) determines the flood insurance premium. On another note, if a building is "substantially damaged" or "substantially improved," it must be brought into full compliance with Unincorporated Lee County’s flood damage prevention regulations, including elevating not just to BFE but also to Freeboard.

Freeboard Definition

Freeboard is a factor of safety (usually expressed in feet) above a required Base Flood Elevation for floodplain management purposes. Newly built (or substantially improved/substantially damaged) structures located in the Special Flood Hazard Area are required to build one additional foot above the FEMA BFE. Freeboard results in significantly lower flood insurance rates due to lower flood risk.

If your home or business is in the SFHA and is below Freeboard, will your proposed improvements/repairs trigger the substantial improvement/substantial damage rule (aka 50% Rule)? Refer to the information below to find out.  

At the time of permitting, if your structure is already  flood compliant (if the lowest floor of the structure, including electrical and mechanical equipment and bathroom are already above Freeboard elevation and enclosed areas below BFE have proper hydrostatic relief), the building can be repaired and reconstructed without having to comply with the 50% Rule. Flood compliance may be confirmed through an elevation certificate**.  Lee County may already have an EC on record. See above blue icon box link named “Find an Elevation Certificate (if on record).”

At the time of permitting, if your structure is NOT flood compliant and the work being proposed exceeds the 50% rule, the building must be elevated to, or above Freeboard. Likewise, all electrical and mechanical equipment (heating and cooling, etc.), bathrooms, and laundry rooms must be elevated to, or above, Freeboard level. Only parking, building access and limited, incidental storage is allowed below the flood level. Non-residential buildings in flood zones beginning with “A” may be “flood proofed” instead of being elevated. (Flood proofing is not permitted in V zones).

**Before purchasing a new Elevation Certificate, check to see if the proposed work will even come close to breaching the 50% rule.

Permit submittal reviews:

At the time of permit application, Unincorporated Lee County will use the assessed value of your structure (excluding the land) recorded by the Property Appraiser’s Office. If you disagree with the Property Appraiser’s Valuation of the structure, you may engage a State of Florida licensed property appraiser to submit a comparable property appraisal for the depreciated value of the structure.

We will evaluate the cost of improvements or repairs and determine if they are fair and reasonable. For damage repairs, pre-storm prices and rates will be utilized. (See above blue icon box link named “Residential FEMA Calculation Valuation Table”).

The cost of improvements or repairs does not include items not considered a permanent part of the structure (i.e., plans, surveys, permits, sidewalks, pools, screens, sheds, gazebos, fences, etc.).

If it has been determined that your structure has incurred “substantial damage” or your proposed remodel/renovation work is considered to be "substantial improvement”, flood compliance must now be achieved. If you suspect that your structure may already be compliant, please coordinate with staff. (Note: typically an Elevation Certificate will prove whether or not a structure is flood compliant. Before paying for a new Elevation Certificate, speak with a certified floodplain manager currently on staff). Note: Garages and Carports are not considered to be the "lowest floor". 

If your proposed project is too close to the 50% threshold to determine if work is considered to be Substantial Improvement, then you will be asked to obtain and submit to us a detailed and complete cost estimate for the addition, remodeling, reconstruction of the structure, prepared and signed by the contractor. The contractor must sign an affidavit indicating that the cost estimate submitted includes all damages or all improvements to your structure, not just structural. If the owner is the contractor, the owner is responsible for submitting the cost estimate and providing documentation, including subcontractor bids, to document the cost estimate.

If the proposed project is not flood compliant, the building plans must be prepared to show how the building is to meet compliance.

If structure is located in a V-zone, Coastal High Hazard Area, or if the non-residential building is to be flood proofed, these building plans must be prepared and certified by a registered professional engineer or architect.

See above blue icon box link named “Detailed Cost Breakdown Package”

Donated or Discounted Materials

The value placed on materials should be equal to the actual or estimated cost of all materials to be used. Where materials or servicing equipment are donated or discounted below normal market values, the value should be adjusted to an amount equivalent to that estimated through normal market transaction.

Self or Volunteer Labor

The value placed on labor should be equal to the actual or estimated labor charge for repairs of all damages sustained by the structure. Where non-reimbursed (volunteer) labor is involved, the value of the labor should be estimated based on applicable minimum hourly wage scales for the type of construction work to be completed. The current average labor rate is approximately $15.00 per hour.

For more detailed information about SI/SD through FEMA’s webpage, see above blue icon box link named “FEMA’s SI/SD webpage.”

Will your proposed improvements or repairs trigger the substantial improvement/substantial damage regulation (aka 50% Rule)?  Refer to the links above to find out more or email for more information.

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