Granny Flat Florida
Zoning Rules, Permits & Costs
Florida calls them ADUs. Same rules, same permits, same zoning laws — whatever name you use. Here’s what you need to know before building one.
What Florida Calls a “Granny Flat”
Florida zoning codes don’t use the term “granny flat.” The official term is Accessory Dwelling Unit (ADU) — defined in Florida Statutes §163.31771 and referenced in every city’s Land Development Code.
A unit triggers ADU rules when it has all four of these: its own entrance, sleeping area, bathroom, and kitchen (sink, cooking appliance, refrigerator) — on the same lot as a primary home. A room with a mini-fridge is not a granny flat. A self-contained cottage in your backyard is.
Florida SB 184 (2025) requires every municipality to allow ADUs by right in single-family residential zones. No city can ban granny flats outright — but each city sets its own size limits, setbacks, and design standards within the state framework.
All the Names for the Same Thing
| What You Call It | Florida Legal Term | Notes |
|---|---|---|
| Granny flat | Accessory Dwelling Unit (ADU) | Most common informal term in Florida |
| In-law suite | ADU or Accessory Apartment | If self-contained with own entrance + kitchen |
| Mother-in-law suite | ADU or Accessory Apartment | Same as in-law suite |
| Casita | Detached ADU / Guest Cottage | Common in South Florida and Hispanic communities |
| Backyard cottage | Detached ADU | Used statewide, especially in marketing |
| Guest house | Detached ADU or Guest Cottage | Must meet ADU standards to be a legal dwelling |
| Carriage house | Detached ADU | Historic neighborhoods; may need historic review |
| Garage apartment | Attached or Detached ADU | Above or beside garage |
| Second dwelling unit | ADU | Melbourne and some county codes use this exact phrase |
Are Granny Flats Legal in Florida?
Yes — and they’ve been getting more legal every year. Two laws changed the landscape:
Florida HB 1339 (2023)
Required all Florida municipalities to allow ADUs in single-family zones. Prohibited owner-occupancy mandates. Set minimum standards cities must honor.
Florida SB 184 (2025, effective July 1, 2025)
Strengthened ADU rights further. Prohibited municipalities from imposing size limits below 1,000 sq ft. Required by-right approval for compliant applications — no discretionary hearings that could delay or kill your project.
HOAs are a separate issue
Florida’s ADU laws don’t preempt HOA deed restrictions. If your HOA prohibits accessory structures or secondary dwellings in its CC&Rs, you cannot build a granny flat regardless of what state law allows. Check your CC&Rs before spending anything on design.
Size Limits & What It Costs to Build
Florida sets a floor of 1,000 sq ft — cities can allow larger, but cannot mandate smaller (with limited exceptions for flood zones). In practice, most Florida cities cap granny flats between 600 sq ft and 1,200 sq ft.
- County impact fees (transportation, schools, fire): $3,000–$8,000+ in most Florida counties
- Florida-licensed architect / engineer: $3,000–$8,000+ (no free plans programs except Gainesville and Orange County)
- Cape Coral utility connection assessments: $10,000–$30,000+ for unassessed parcels
- HVHZ wind load compliance (South Florida, coastal counties): adds $10,000–$25,000 in impact windows, doors, and roof systems
Granny Flat Rules by Florida City
Each city sets its own rules within Florida’s state framework. Click any city for the full guide.
| City | Max Size | Owner Occupancy | STR |
|---|---|---|---|
| Orlando | 1,000 sq ft | Not required | 30-day min |
| Tampa | 1,500 sq ft (RS-50+) | Not required | 30-day min |
| Jacksonville | Varies by district | Not required | Verify |
| Miami | 750 sq ft (HVHZ zones) | Verify by district | Restricted |
| Gainesville | ~850 sq ft (city) | Not required (city) | Verify |
| Tallahassee | 1,200 sq ft | Not required | Allowed |
| St. Petersburg | 800 sq ft / 67% of primary | Verify | 30-day min |
| Fort Lauderdale | 600 sq ft / 49% of primary | Required | Prohibited <30 days |
| West Palm Beach | ~800 sq ft (SF14 only) | Verify | 6 months + 1 day min |
| Melbourne | Smaller than primary / ~1,000 sq ft | Not required | Currently unregulated |
| Cape Coral | Verify with city | Verify | Verify |
| Daytona Beach | 50% of primary | Required | Prohibited <30 days |
Data as of June 2026. Verify current rules with city planning before committing to design.
Rental Income from a Florida Granny Flat
A granny flat in Florida typically rents for $950–$2,000/month long-term, depending on city, size, and condition. Higher-income markets (Palm Beach, Fort Lauderdale, Miami) command premiums. Stable workforce markets (Space Coast, Gainesville, Tallahassee) offer lower but more consistent yields.
| Market | 1-Bed Long-Term Rent | Demand Driver |
|---|---|---|
| Miami / Fort Lauderdale | $1,800–$2,500/mo | Urban professionals, healthcare, finance |
| West Palm Beach | $1,700–$2,200/mo | High-income Palm Beach County market |
| Orlando | $1,300–$1,700/mo | Tourism, tech, UCF — year-round demand |
| Tampa / St. Petersburg | $1,400–$1,900/mo | Booming metro, remote workers, healthcare |
| Jacksonville | $1,100–$1,500/mo | Military, logistics, finance — stable |
| Melbourne / Palm Bay | $1,100–$1,500/mo | SpaceX, NASA, aerospace professionals |
| Gainesville | $900–$1,300/mo | University of Florida — dense student + staff demand |
| Tallahassee | $950–$1,300/mo | FSU, FAMU, state government employees |
| Cape Coral | $1,200–$1,700/mo | Retirees, snowbirds, Gulf Coast lifestyle |
How to Permit a Granny Flat in Florida
The permitting process is similar across Florida cities, with variations in portal names and timelines. The core steps:
Check your zoning and verify your city
Use your city's GIS map to confirm your zoning district and that you're in the right jurisdiction (not unincorporated county, not a neighboring city). This determines which rules and permit office apply.
Confirm ADU eligibility
Call your city's Planning or Zoning department. Ask: is an ADU permitted by right in my district? What are my setbacks, lot coverage limit, and maximum ADU size? 15 minutes on the phone can save months of wasted design work.
Check your HOA CC&Rs
If your property has an HOA, review the CC&Rs for restrictions on accessory structures or secondary dwellings. City permits do not override HOA covenants.
Hire a Florida-licensed designer
Most Florida cities require construction drawings signed and sealed by a Florida-licensed architect or Professional Engineer. Exception: Gainesville and Orange County offer free pre-approved plan sets you can use without hiring a designer.
Submit building permit application
Submit via your city's online permit portal with the required documents: property survey, construction drawings, site plan, energy calculations (RESCHECK), contractor license.
Record Notice of Commencement
Required by Florida law before construction begins. Record with your county Clerk of Courts and post on-site.
Inspections and Certificate of Occupancy
Schedule required inspections at each construction phase. After passing the final inspection, the city issues a Certificate of Occupancy — the unit is now a legal dwelling.
Frequently Asked Questions
What is a granny flat called in Florida zoning law?
Florida zoning codes call granny flats "Accessory Dwelling Units" (ADUs) or "Accessory Apartments." Some cities use their own terms: Melbourne calls them "Second Dwelling Units," Pinellas County uses "Accessory Dwelling Unit" in Chapter 138. Regardless of what you call it, the legal test is the same: a self-contained unit with its own entrance, sleeping area, bathroom, and kitchen on the same lot as a primary home.
Are granny flats legal in Florida?
Yes. Florida SB 184 (2025) requires every municipality to allow ADUs (granny flats) by right in single-family residential zones. Cities cannot ban them outright. However, they can impose size limits (minimum 1,000 sq ft floor, but cities may set lower caps in some cases), setback requirements, and design standards. HOA deed restrictions are independent of government permits and can still prohibit granny flats — check your CC&Rs.
How big can a granny flat be in Florida?
Florida SB 184 (2025) prohibits municipalities from imposing ADU size limits below 1,000 sq ft. However, individual cities may set their own caps: Fort Lauderdale caps at 600 sq ft, St. Petersburg at 800 sq ft, Palm Bay at 800 sq ft or 50% of primary home, Daytona Beach at 50% of primary home. Tallahassee allows up to 1,200 sq ft. Your specific city's rules apply — check your address.
What does it cost to build a granny flat in Florida?
Building a granny flat (ADU) in Florida typically costs $80,000–$300,000+ depending on size, type, and location. A garage conversion is the least expensive ($40,000–$100,000). A new detached cottage runs $120,000–$250,000. A two-story above-garage unit can reach $200,000–$350,000+. South Florida (Miami, Fort Lauderdale) costs are highest due to HVHZ wind load requirements and labor costs. Add $3,000–$8,000+ for Brevard, Broward, Palm Beach, and Lee County impact fees.
Do I need a permit to build a granny flat in Florida?
Yes, always. An unpermitted granny flat is illegal, creates title problems when you sell, voids your homeowner's insurance, and can result in fines or forced removal. All Florida granny flats require a building permit, plans sealed by a Florida-licensed architect or engineer, and a Certificate of Occupancy before anyone can legally live in the unit.
Can I rent out a granny flat in Florida?
Yes, in most Florida cities long-term rental of a granny flat is allowed. Short-term rental rules vary significantly: Orlando requires 30-day minimum, Fort Lauderdale prohibits STR under 30 days, West Palm Beach requires 6 months + 1 day, Tallahassee allows STR, Melbourne currently has no specific local STR ordinance. All STR operators statewide need a Florida DBPR Vacation Rental Dwelling license and must collect Florida 6% sales tax plus the applicable county Tourist Development Tax.
What is the difference between a granny flat and an in-law suite in Florida?
In Florida zoning law, there is no legal distinction — both terms describe an Accessory Dwelling Unit (ADU). The practical difference is construction type: "in-law suite" often implies an interior conversion (converted bedroom or basement with added kitchen), while "granny flat" usually implies a detached or attached separate structure. Both require permits and must meet ADU zoning standards. An in-law suite that shares an entrance with the primary home and has no separate kitchen is typically not classified as an ADU.
Granny Flat Guides by Florida City
Check If Your Property Qualifies
Enter your Florida address for a free zoning eligibility check — see which ADU types are permitted, setback requirements, and local rules for your specific parcel.
Also see: Florida ADU Laws 2025 · Cost to Build an ADU · Airbnb ADU Rules by City