Building permits, zoning and septic rules in Martin County, Florida

Unincorporated Martin County, Florida requires a building permit before regulated construction, enlargement, alteration, repair, movement, demolition or a change in occupancy; regulated electrical, gas, mechanical and plumbing work also requires a permit¹. Martin County has adopted the Florida Building Code, 8th Edition (2023), effective December 31, 2023, along with Martin County amendments¹⁰. The code is adopted statewide for use in Martin County without separate local adoption; if an application predates a code update, the code in effect when the application was submitted governs that work for the life of the permit and any extension¹¹. County authority applies outside incorporated municipalities, while a city may be the permitting jurisdiction inside its limits¹². Work exempt from a building permit is governed by the Florida Building Code; ask the Building Department whether a proposed repair qualifies before starting¹. A nonresidential farm building on land used for bona fide agriculture may also be exempt from the Florida Building Code and county code or fees, but the exemption does not cover a dwelling or displace floodplain rules⁹.

The Martin County Building Department handles building permits for unincorporated Martin County and can be reached Monday through Friday, 7 a.m. to 4:30 p.m., at 772-288-5916¹. You can submit most permits at the permit counter or electronically, whether it's a small home project or new construction¹. A qualifying owner-builder must appear in person at the Building Department, located at 900 SE Ruhnke Street in Stuart, to sign the Building Permit Application and Owner/Builder Disclosure; later transactions may be completed electronically¹. Martin County issues building permits to licensed contractors in good standing or qualifying owner-builders applying in place of a licensed contractor¹. For permits that need plan review, the application is routed to the relevant departments before approval, building-permit issuance and field inspections¹. The county's fee schedule effective July 1, 2026 starts at a $75 building fee and a $25 plan review fee for construction costs under $25,000, plus $75 for each inspection, and a $250 building fee and $200 plan review fee for costs of $50,001 to $150,000; state surcharges are extra³.

Martin County Growth Management administers zoning in unincorporated areas^2,6. The Village of Indiantown and Town of Jupiter Island have their own zoning rules; septic permitting remains with the Florida Department of Health in Martin County^4,13,14. For unincorporated land, use the county's Future Land Use and Zoning Map: the future-land-use designation controls when it conflicts with zoning². In the A-2 Agricultural District, the general minimum lot area is 5 acres, subject to recorded-subdivision exceptions, and front, rear and side yards are generally 25 feet, with right-of-way and water-frontage provisions¹⁵. Environmental buffers and additional setbacks may also apply². We could not confirm a countywide minimum dwelling size or complete accessory-dwelling rule; Florida's authorization for local accessory-dwelling ordinances does not itself authorize a unit on a Martin County parcel^6,16. Ask Growth Management at 772-288-5495 to confirm the parcel's jurisdiction, zoning, lot standards and setbacks before designing or buying⁶.

The Florida Department of Health in Martin County continues septic-tank permitting and inspections, while the Florida Department of Environmental Protection implements the governing statutes and regulations⁴. Installing, replacing, repairing, modifying or abandoning a septic system requires the applicable permit, and a site evaluation determines the parcel conditions and system suitability¹⁷. Operating permits are required for aerobic treatment units, performance-based treatment systems, commercial septic systems, and systems on industrial- or manufacturing-zoned property or its equivalent⁴. An owner, or a contractor authorized by the owner, may hire a private provider for an OSTDS inspection⁴. Reach the Stuart health office at 772-221-4000 or 3441 SE Willoughby Blvd., Stuart, FL 34994¹⁸. Only about 0.6% of Martin County soils are rated without severe limitations for a conventional septic drain field, so make septic feasibility a purchase contingency¹⁹. If public sewer later becomes available, a properly functioning onsite system generally must connect within 365 days after written notice, with different timing for a system needing repair or modification²⁰.

Florida regulates transient stays in permitted recreational vehicle parks and recreational camps, but that statewide rule does not establish permission to occupy an RV on private land in Martin County⁵. We could not confirm a countywide private-land RV or temporary-camping rule, so ask Growth Management about the parcel's zoning district before relying on an RV during construction⁶. In the A-2 Agricultural District, county rules allow a trailer only on at least 20 acres, with one trailer per lot, a 100-foot setback from property lines, agricultural principal use, residential use only and required screening; ask Growth Management whether an RV or tiny house on wheels counts as a trailer there^6,15. Martin County allows tiny homes as eligible units in SHIP-funded affordable rental new-construction or rehabilitation developments, subject to the program’s compliance requirements²¹. That program does not establish a general right to occupy a tiny home on private land; we could not confirm the broader occupancy rule or a countywide minimum dwelling size, so ask Growth Management about the proposed unit^6,21. A tiny home involving regulated construction still needs the applicable building permit, and its proposed residential use must fit the parcel's zoning^1,2. An off-site-constructed dwelling, including a qualifying manufactured home treated as real property, must be permitted as of right where single-family detached homes are allowed, but it remains subject to generally applicable permitting, installation, health, utility and zoning requirements²².

1. Confirm whether the parcel is in unincorporated Martin County or a municipality, because the local zoning authority and rules may differ².
2. Ask Growth Management to identify the future-land-use designation, zoning district, district setbacks and any added environmental buffers^2,6.
3. Determine water and sewer service. Apply through Martin County Health for septic permitting and inspection, and obtain the required permit for construction, repair or abandonment of a private well^4,7.
4. Choose a licensed contractor or determine whether you qualify as an owner-builder; a qualifying owner-builder must sign the application and disclosure in person at 900 SE Ruhnke Street¹.
5. Submit the building application at the counter or electronically; plans needing review are routed to the appropriate departments, and approval precedes building-permit issuance and field inspections¹.
6. Complete the required field inspections. A qualifying threshold building also needs structural inspections under an approved plan by a special inspector selected and paid by the owner^1,23.
7. Ask the Building Department which final approval or certificate applies before occupancy; the county confirms that it schedules an inspection associated with a Certificate of Occupancy²⁴.

Martin County's median property tax bill is about $3,120 a year at an effective rate near 0.8%, while the typical annual home-insurance premium is about $5,268¹⁹. About 24.3% of the county is federally owned, so confirm that the parcel and its access are private and legally usable¹⁹. Martin County averages about 55.6 inches of precipitation a year, and only about 0.6% of its soils rate without severe conventional-septic limitations; make drainage and septic feasibility contract contingencies where possible¹⁹. A private well needs a permit for construction, repair or abandonment, with Martin County among the counties where the health department has delegated well-permitting work^7,8. Florida regulates subdivision and platting statewide and allows additional local requirements, so ask Growth Management before assuming a tract can be split^6,25. We could not confirm the complete Martin County driveway or floodplain-development rules; ask Growth Management which office must review access and floodplain work for the parcel⁶.