Martin County, FL Building Setbacks & Zoning: Setback Rules (2026)
Key Facts
- Governing table
- LDR Table 3.12.2, Structure Setbacks
- RS-3 front setback
- 25 feet minimum
- RS-3 side/rear setback
- 10 feet minimum
- U.S. Highway 1 centerline setback
- 100 feet
- Waterfront (WE-1) setback
- 50 feet from mean high water
- Enforcing agency
- Growth Management Department
Summary
LDR Section 3.16 requires every structure to sit back from lot lines at least as far as Table 3.12.2 specifies for its zoning district, with the front setback applying to every side of a lot touching a street. A standard RS-3 single-family lot needs a 25-foot front setback and 10-foot side and rear setbacks.
3.16.A.General requirements.1.Structures shall be set back from lot lines at least as far as the distance indicated in Table 3.12.2.2.The front setback as shown in Table 3.12.2 shall apply to all sides of a lot which are adjacent to a street. However, where the lot was lawfully established prior to May 9, 1967, and is 75 feet or less in width, as measured along the front lot line, or which is otherwise 7,500 square feet or less in total area, the front setback shall only apply to the sides of the lot providing vehicular access.3.Except as set forth in subsection 3.16.B below, every part of every required front, side and rear setback shall be comprised of open space.4.Where any building site consists of an unplatted parcel of less than a platted lot or where it takes in more than one platted lot, the setbacks required herein shall apply to the building as a whole.
Official source re-checked September 7, 2026: no newer edition of the code had been published (publisher’s edition: Code of Ordinances: Supplement 62 | Land Development Regulations: Supplement 62).
Full Breakdown
2, Structure Setbacks, sets front, rear and side distances by zoning district and, for multi-story buildings, by story. In the RS-3 district the minimums are 25 feet front, 10 feet rear and 10 feet side; RS-6 through RM-10 districts start at the same 25-foot front and 10-foot side/rear on the first story but step up on additional stories, reaching 40-foot rears and 30-foot sides by the fourth story. 12 footnotes require a 25-foot setback from the mean high water line in the R-1 and R-1B districts and a 50-foot setback in WE-1.
2 applies the front setback to every side of a lot abutting a street, except that lots platted before May 9, 1967 that are 75 feet or less wide, or 7,500 square feet or smaller, need only meet the front setback on the side with vehicular access. B lists what can sit inside a required setback anyway: trees and landscaping, code-compliant fences, driveways and sidewalks, docks, screened wells, signs, underground utility lines, HVAC and generator equipment that can intrude up to half the setback (never closer than three feet to the line), and roof overhangs, gutters, cantilevered balconies, awnings and chimneys that can project up to three feet. S. Highway 1, unless the lot is served by a utility structure or a right-of-way platted before April 29, 1986.
Violations & Fines
Growth Management verifies setbacks at site plan and building permit review, and re-checks them at the survey stage before a certificate of occupancy issues. A structure built inside a required setback without an approved exception under Section 3.16.B is a zoning violation subject to code enforcement, which can order removal or relocation of the encroaching structure and impose fines through the special magistrate process until the property is brought into compliance.
Frequently Asked Questions
How far back from the property line must I build in a Martin County RS-3 subdivision?
Can my air conditioning unit sit inside the required side setback?
What setback applies along U.S. Highway 1 in Martin County?
Sources & Official References
Other rules in Martin County
Florida rules heatmap·Compare Martin County to another location·View the Florida building setbacks & zoning overview
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