Substantial Damage/Improvement Guidelines

Hillsborough County is a qualifying community under the National Flood Insurance Program (NFIP) by adopting and enforcing regulations and codes that apply to all development within the Special Flood Hazard Area (SFHA). The county’s NFIP participation requires strict adherence to implement floodplain management practices that exceed the Federal minimum program requirements of the NFIP to provide protection from flooding. The County also participates in the Community Rating System (CRS), a credit criteria-based incentive program. The purpose of the CRS program is to support the NFIP regulations and our participation in the CRS provides discounts on NFIP flood insurance premiums. As an NFIP requirement, Hillsborough County has adopted a Floodplain Management Ordinance. The County also enforces the Florida Building Code. For development requirements for buildings in SFHAs, please reference the Florida Building Code, as modified by Chapter 3 of the Hillsborough County Construction Code (HCCC), and the LDC 3.06.00 for the Flood Damage Control Regulations.

The FBC Existing Building Code specifies requirements for work on existing buildings in SFHAs. When work on an existing building is determined to be substantial improvement, or damage is determined to be substantial damage, the FBC requires those buildings to be brought into compliance. The HCCC Chapter 4 defines Substantial Improvement and Substantial Damage (see page 5). In sum, when the cost of improvements equals or exceeds 50 percent of the market value of the structure before the “start of construction” of the improvement, the project will be deemed a substantial improvement. Similarly, when the cost to repair a building damaged by any cause equals or exceeds 50 percent of the market value of the building before the damage occurred, the building will be deemed substantially damaged. In addition, the cost of any previous work (during a 12-month period following the date of final inspection) shall also be added to the cost of the improvement, to include overhead and profit. When work is determined to be substantial improvement or repair of substantial damage, the existing structure must be brought into compliance with the FBC and the HCCC Flood Damage Control Regulations.

To determine if buildings are in flood zones, and applicable base flood elevation(s) (BFE), use the County GIS or visit the FEMA Flood Map Service Center.

Substantial Improvement/Substantial Damage Worksheets completed by the owner and contractor will be evaluated with the permit application to determine if the proposed scope of work constitutes a substantial improvement or repair of substantial damage:

1. Complete the Substantial Improvement/Substantial Damage Worksheet. Ensure all pages are legible. Indicate the owner’s name, property address and if the scope of work is an addition, alteration, or repair and the year the structure was built. Information can be obtained from the Hillsborough County Property Appraiser website.
2. Complete and sign the Contractor and Owner Attestation. Include overhead and profit.
3. Complete the Substantial Improvement/Substantial Damage Cost Breakdown.
4. Complete the Substantial Improvement Calculator line items A-F:

• Line Item A: Building Market Value from the (or provide a current Certified Appraisal)
• Line Item B: Proposed Project Cost from the Contractor and Owner Attestation
• Line Items C through E: List the total cost of any past improvements during a 12-month period following the final inspection date
• Line Item F: Total line items B through E

Substantial Improvement / Damage Cost Breakdown Items

Items to be included in estimating costs

The following list of costs that must be included is not intended to be exhaustive, but characterizes the types of costs that must be included:

• Material and labor, including the estimated value of donated or discounted materials and owner or volunteered labor
• Site preparation related to the improvement or repair
• Demolition and construction debris disposal
• Labor and other costs associated with demolishing, moving or altering building components to accommodate improvements, additions and making repairs
• Costs associated with complying with any other regulation or code required that is triggered by the work, including cost to comply with the requirements of the Americans with Disabilities Act (ADA)
• Construction management and supervision
• Contractors overhead and profit
• Sales taxes on materials
• The cost of any previous work (during a 12-month period following the date of final inspection) shall also be added to the cost of the improvement, to include overhead and profit

Notice to property owners, contractors and design professionals; the value placed on all donated or discounted materials must be equal to the actual or estimated cost of such materials and must be included in the total cost of improvements. The value of donated or discounted materials must be equivalent to normal market values.

Property owners that undertake the improvements and repair project on their own must include the volunteer labor in the total cost of improvements. The rate must be equivalent to the normal market value or the going rate for labor. The value placed on labor must be estimated based on applicable minimum-hour wage scales for the skill and type of construction work that is done.

All structural elements and exterior finishes, including but not limited to:

• Foundations (e.g., excavation, spread or continuous foundation footings, perimeter walls, chain-walls, pilings, columns, posts, pilings, etc.)
• Monolithic or other types of concrete slabs
• Bearing walls, tie beams and trusses
• Joists, beams, subflooring, framing and ceilings
• Interior non-bearing walls
• Exterior wall finishes (e.g., brick, stucco, siding, painting, trim and decorative molding)
• Windows and exterior doors
• Roofing, gutters and downspouts
• Hardware
• Attached decks and porches

All interior finish elements, including but not limited to:

• Floor finishes (e.g., hardwood, ceramic, vinyl, linoleum, stone and wall-to-wall carpet over sub-flooring)
• Bathroom tiling and fixtures
• Wall finishes (e.g., drywall, paint, stucco, plaster, paneling, marble or other decorative finishes)
• Built-in cabinets (e.g., kitchen, utility, entertainment, storage and bathroom)
• Interior doors
• Interior finish carpentry
• Built-in bookcases and furniture
• Hardware
• Insulation

All utility and service equipment, including but not limited to:

• Heating, ventilation and air conditioning (HVAC) equipment
• Plumbing fixtures and piping
• Electrical wiring, outlets and switches
• Light fixtures and ceiling fans
• Security systems
• Built-in appliances
• Central vacuum systems
• Water filtration, conditioning and recirculation system

Items that can be excluded

• Costs to obtain or prepare plans and specifications
• Land survey costs
• Permit fees and inspection fees
• Debris removal (e.g., removal of debris from building or lot, dumpster rental, transport fees to landfill and landfill tipping fees)
• Clean-up (e.g., dirt and mud removal, and building dry out)
• Carpeting and recarpeting installed over finished flooring such as wood or tiling
• Outside improvements, including landscaping, irrigation, sidewalks, driveways, fences, yard lights, swimming pools, pool enclosures and detached accessory structures (e.g., garages, sheds and gazebos)
• Plug-in appliances (e.g., refrigerators, washing machines, dryers and stoves)
• Costs to temporarily stabilize a building so that it is safe to enter to evaluate and identify required repairs
• Land value
• Costs of any project for improvement of a structure to correct existing violations of state or local health, sanitary, or safety code specifications which have been identified by the local code enforcement official and which are the minimum necessary to assure safe living conditions

HBBC Chapter 4 Definitions

• Substantial damage. Damage of any origin sustained by a building or structure (including a manufactured home) whereby the cost of restoring the building or structure (or manufactured home) to its before-damaged condition would equal or exceed 50 percent of the market value of the building or structure (or manufactured home) before the damage occurred
• Substantial improvement. Any combination of repair, reconstruction, rehabilitation, alteration, addition or other improvement of a building or structure taking place during a twelve (12) month period, the cumulative construction cost of which equals or exceeds 50 percent of the market value of the building or structure before the improvement or repair is started. The period of accumulation begins when the permit for the first improvement or repair of each building is issued through the 12 month period following the issuance of the Certificate of Occupancy or final inspection (whichever dates provides the longest period). If the building or structure has incurred "substantial damage", any repairs are considered substantial improvement regardless of the actual work performed. However, the term does not include either:

1. Any project for improvement of a structure to correct existing violations of state or local health, sanitary, or safety code specifications which have been identified by the local code enforcement official and which are the minimum necessary to assure safe living conditions; or
2. Any alteration of a "historic structure" provided that the alteration would not preclude the structure's continued designation as a "historic structure."

• Market value; the term refers to the market value of buildings and structures, excluding the land and other improvements on the parcel. Market value is the Actual Cash Value (in-kind replacement cost depreciated for age, wear and tear, neglect, and quality of construction) determined by a qualified independent appraiser, or the tax assessment value adjusted to approximate market value by a factor provided by the County Property Appraiser’s Office. (Reference; HCCC Chapter 4 Definitions)
• Design Flood Elevation; the elevation of the “design flood,” including wave height, relative to the datum specified on the Hillsborough County flood hazard map or otherwise legally designated in the Hillsborough County Stormwater Technical Manual. In areas designated as Zone AO, the design flood elevation shall be the elevation of the highest existing grade of the building’s perimeter plus the depth number (in feet) specified on the flood hazard map. In areas designated as Zone AO where the depth number is not specified on the map, the depth number shall be taken as being equal to 2 feet. (Reference; HCCC Chapter 4 Definitions)
• Cumulative construction cost. The sum total of costs associated with any construction work done to a building or structure either at one (1) time or at different times within a specified period of time. For floodplain management purposes, cumulative construction costs are costs associated with an approved project regardless of the period required to complete the project and/or, costs associated with the development of construction work done to the building from the time the permit application is submitted through the 12 month period following the issuance of the Certificate of Occupancy or final inspection (whichever date provides the greatest period).

Complete the Substantial Improvement Substantial Damage Worksheet