Floodplain rules · Fort Worth
Remodeling in a floodplain in Fort Worth
A Fort Worth house in the FEMA floodplain needs the City’s Floodplain Development Permit before a remodel or addition. If the work costs half the building’s market value or more, the whole house has to meet the floodplain rules for a new one.
Or call or text (817) 631-9803
From the City of Fort Worth Code (chapter 7, sections 7-304, 7-333 and 7-347), its stormwater review page, FEMA’s rule at 44 CFR 59.1 and FEMA’s substantial damage guide, all read November 7, 2026.
The 50 percent rule
What is FEMA’s 50 percent rule?
It’s the test for a house that’s already in the floodplain. If the cost of a rebuild, remodel, addition or other improvement equals or exceeds 50 percent of the building’s market value before the work starts, FEMA and the City call it a substantial improvement.
- The building’s market value · The house alone, before the work starts
- The land · Not counted
The cost of the work
- Under 50% · The City says the house may be remodeled without meeting the floodplain rules
- 50% or more · The City says the entire house must be brought into compliance with its floodplain rules
What counts in the cost
- Materials and labor, including donated or discounted materials and work you or volunteers do, at what it’s worth
- Structural work, demolition and hauling away the debris
- The contractor’s overhead and profit
- Utility and service equipment
- Interior and exterior finishes
- Work the codes require
What counts as the value
- The market value of the building only
- Not the land, and not site improvements
“Any value associated with the location of the property should be attributed to the land, not the building.”
The cost side of the test is the whole project. We price the whole job with you.
Past 50 percent
What happens when a Fort Worth remodel crosses 50 percent
The whole house has to meet the City’s floodplain rules, not only the new part. For a house, that starts with the lowest floor.
2 ft
above the higher base flood elevation: the City’s fully developed figure or FEMA’s
- The lowest floor
- Including a basement and a finished garage, at least two feet above the higher of the two flood elevations.
- The equipment
- The machinery and equipment that serve the house, to the same height.
- The proof
- A registered surveyor or engineer certifies it to the City’s floodplain administrator.
5 years
When the work stays under 50 percent, the City tracks later work on the house for five years once it issues a floodplain permit using the 50 percent rule. Together, that work can’t pass 50 percent of the house’s fair market value when the first permit was issued.
Planning an addition now and a kitchen later? Walk the whole plan with us first.
The permit
Fort Worth floodplain development permit: what the City asks for
The City Code says no one may develop property in the floodplain until they’ve applied for and been issued a Floodplain Development Permit. Before the City issues it, any state or federal permit the work needs has to be in hand. The application goes to the City’s floodplain administrator, and it asks for:
- Plans to scale showing the existing and proposed structures, their size and elevation, and any change to the ground
- An elevation certificate for a house in or next to the floodplain, from a registered surveyor or engineer, giving the height of the lowest floor, a basement, a finished garage and the equipment that serves the house
- For an existing house that doesn’t meet today’s floodplain rules, the City’s Substantial Improvement or Substantial Damage Review Package, so the City can decide whether the work is a substantial improvement
The code also says the elevation certificate must be submitted within 60 days of finishing the work. A substantial improvement needs a building permit too, from Development Services at 817-392-2222, and the City won’t issue a building permit, an inspection or a certificate of occupancy until the floodplain rules are met.
City Code, chapter 7,
section 7-333,
as amended effective January 23, 2026, read on the City’s code library November 7, 2026. The City’s stormwater page says the permit is filed through Accela and takes 10 business days for a standard review.
Want a designer and a builder to walk the house with you before anyone draws? Start with an estimate.
Before you draw
How to find your Fort Worth house’s flood elevation
Start with the maps, then ask the City what it has on file. The City’s floodplain staff make the final call on what applies to your house.
“Any development in the floodplain without a permit is illegal.”
The City’s map
The City’s Flood Risk Viewer shows the FEMA floodplain and the City’s own flood risk areas.
FEMA’s map
The FEMA Flood Map Service Center is FEMA’s official source for its flood maps, searchable by address.
The City’s file
The City may have an elevation certificate on file. Ask Floodplain Management for a copy at floodplain@fortworthtexas.gov or 817-392-6261. If there isn’t one on file, the City says you’ll need to hire a surveyor or engineer to complete it.
The City’s Flood Risk Viewer shows three kinds of flood risk, and two of them come with rules for building. How the City’s flood risk areas work
Bring us the address, and we’ll look up the flood map at no charge.
Before the drawings
How to plan a remodel or addition in the Fort Worth floodplain
Look up the house, price the work against the building’s value, and apply for the floodplain permit with the building permit.
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Look up the house. Before an offer or a drawing, we look up a house’s address at no charge, flood map included. Then ask the City whether it has an elevation certificate on file.
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Price it against the building. The cost of the whole project, measured against the market value of the house alone. If later phases are coming, count them too: the City tracks five years.
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Apply. The Floodplain Development Permit through the City’s floodplain administrator, with the review package if the house doesn’t meet today’s rules, and the building permit with it.
Adding on to a house in the floodplain? Start with the walk-through.
Questions
Fort Worth floodplain remodeling questions
Planning work on a house in the floodplain? Bring these questions to us.
Do I need a floodplain permit to remodel a house in Fort Worth?
Yes, if the house is in the FEMA floodplain. The City’s Stormwater Criteria Manual requires the permit before any construction work or physical alteration to the house or lot there. The City’s stormwater page says any development in the floodplain without a permit is illegal, and the City’s floodplain staff can tell you what your project needs.
What is a substantial improvement in Fort Worth?
Any reconstruction, rehabilitation, addition or other improvement to a building that costs 50 percent or more of the building’s market value before the work starts. It also covers a house that’s been substantially damaged, whatever the repair. The City’s definition matches FEMA’s. The code lists two exceptions; the City’s floodplain staff can say whether either applies.
Does the land count in the 50 percent rule?
No. FEMA’s guide says only the market value of the structure is counted, and any value from the property’s location belongs to the land, not the building.
How high does a remodeled house in the Fort Worth floodplain have to be?
If the work is a substantial improvement, the City Code puts the lowest floor, including a basement, a finished garage and the equipment that serves the house, at least two feet above the base flood elevation. It uses the City’s fully developed figure or FEMA’s, whichever is higher.
Can I split a remodel into smaller jobs to stay under 50 percent?
The City tracks it. Once a floodplain permit is issued using the 50 percent rule, later work on the house is tracked for five years, and together it can’t pass 50 percent of the house’s fair market value when the first permit was issued.
What is an elevation certificate, and where do I get one in Fort Worth?
It’s FEMA’s form recording how high the lowest floor and the equipment sit, completed by a registered surveyor or engineer. The City’s code asks for one with the floodplain permit application and says it must be submitted within 60 days of finishing. Ask Floodplain Management at floodplain@fortworthtexas.gov whether one is on file; if not, the City says you’ll need a surveyor or engineer to complete it.
Who decides if my remodel is a substantial improvement?
The City. FEMA says local officials make these determinations. In Fort Worth, for an existing house that doesn’t meet today’s floodplain rules, the review package goes to the City’s floodplain administrator with the application to get the substantial improvement determination.
Every rule on this page is quoted or paraphrased from City of Fort Worth Code sections 7-304, 7-333 and 7-347, the City’s stormwater review page, 44 CFR 59.1, FEMA’s Substantial Damage Quick Guide and the FEMA Flood Map Service Center, read November 7, 2026, and the City’s Stormwater Criteria Manual (July 2024), read November 6, 2026. FEMA’s full guidance is its Substantial Improvement/Substantial Damage Desk Reference, P-758.
Your house
Plan your remodel or addition around the floodplain rules
Know the permit, the 50 percent line and the flood elevation before anyone draws. Walk the house with a designer and a builder first, and start with an honest estimate. No charge, no obligation.
Home additions in Fort Worth · Whole-home remodels
Or call or text (817) 631-9803