ADU Permits in Florida: What HB 1339 Changed for Homeowners

If you've searched "HB 1339 ADU Florida," you've probably found a dozen sites confidently explaining what this law changed. Here's the problem: there's no Florida bill by that number that mandates ADUs statewide. It doesn't exist. That name has spread across enough blogs and AI-generated content that it now shows up as fact, but it isn't one, and repeating it doesn't help you figure out what you can actually build.

Here's what's real. Florida does have a state ADU statute, Section 163.31771 of the Florida Statutes, but it's permissive, not mandatory: it says a local government "may" adopt an ordinance allowing ADUs, not that it must. Twice in the past two years, lawmakers tried to turn that "may" into a "shall." Both attempts died before becoming law. So Florida's ADU landscape today looks a lot like Texas's: no statewide right to build one, city-by-city rules, and a real chance your city has already said yes even without a state mandate forcing it to.

Below: what the actual legislative history is, what Miami, Tampa, Orlando, and Jacksonville each currently allow, and why hurricane wind-load requirements are the single biggest Florida-specific cost factor in any ADU project.

What actually happened with Florida's ADU legislation

Two real bills tried to do what "HB 1339" is credited with online, and it's worth knowing both, because a similar bill is expected to return.

Senate Bill 184 (2025 session). This bill would have changed Section 163.31771 from "a local government may adopt an ordinance" to "a local government shall adopt an ordinance", turning permission into a mandate, with a deadline for cities to comply. It moved through committees and passed engrossment, but according to the Florida Senate's own bill history, it died in returning messages on June 16, 2025. It did not become law.

Senate Bill 48 (2026 session). The follow-up attempt. It would have required every county and municipality to adopt an ADU ordinance by December 1, 2026, banned outright prohibitions on ADUs, and eliminated blanket owner-occupancy requirements. It passed the Senate 38–0, as close to unanimous as legislation gets, and reached the House. On the last day of the 2026 session, March 13, the House couldn't resolve a dispute over a short-term rental provision attached to the bill, and it died rather than pass with that language intact. It did not become law either.

What this means for you right now: there is no statewide mandate. Section 163.31771 is still permissive. Whatever your city allows, it allows because your city chose to adopt its own ordinance, not because state law forced it to. Given how close both bills came, something similar is widely expected to return in the 2027 session. If it passes, it would meaningfully change several of the city rules below, particularly around owner-occupancy. Confirm current status before assuming anything here still holds a year from now.

Florida ADU regulations: the state-level picture (accurate version)

A few things are true across Florida regardless of city, and a few things are genuinely locally determined, the distinction matters.

No statewide size, setback, or owner-occupancy mandate exists today. Every city sets its own numbers. Miami-Dade, Orlando, Jacksonville, and Tampa all require some form of owner-occupancy, but the exact rule (which residence, and for how long) varies by city, and other Florida cities may not require it at all. This is the opposite of what a lot of "Florida ADU law" content claims.

Rental income and homestead exemption: Section 196.061, Florida Statutes treats renting "all or substantially all" of a homestead property as abandonment of the exemption, but an ADU is a secondary structure, not the whole homestead, so renting one alone generally should not trigger that provision. That said, SB 48 (2026) would have added an explicit statutory guarantee protecting the homestead exemption when an ADU is rented, which tells you the point is closer to "generally understood" than "settled law." Confirm your specific situation with your county property appraiser before renting. Separately, rental income is taxable; talk to an accountant about how it affects your filing.

HOA and deed restrictions sit outside any of this legislation, proposed or enacted. Zoning changes, whether a city ordinance or a state mandate like the ones proposed in SB 184 and SB 48, govern what your local government allows. They don't override a private HOA's or subdivision's recorded covenants. If your HOA's CC&Rs prohibit accessory structures or secondary dwellings, that restriction holds regardless of what your city's zoning code says or what the legislature does. This is the single most common surprise for Florida ADU projects, and it deserves the same emphasis whether or not a state mandate ever passes.

Florida's hurricane and wind-load requirements apply everywhere, and they don't come from any of this ADU-specific legislation, they come from the Florida Building Code. This is the piece that makes Florida ADU design meaningfully different from most other states, and it's covered in its own section below.

Miami ADU rules (2026)

• Status: Allowed in unincorporated Miami-Dade County under an ordinance the County Commission approved in November 2022, codified in Miami-Dade County Code Section 33-22.
• Size limit: In unincorporated Miami-Dade's RU-1 districts, between 400 and 800 sq ft, per the county's official ADU program.
• Lot size minimum: 7,500 sq ft for new construction.
• Setbacks: Commonly cited around 5 ft in RU-1 districts. Confirm your specific district with the Miami-Dade Building Department.
• Parking: At least one off-street space required.
• Owner-occupancy: Required in unincorporated Miami-Dade, but specifically of the primary home. The property owner cannot reside in the ADU itself.
• Wind-load compliance: Miami-Dade sits in Florida's High-Velocity Hurricane Zone (HVHZ), the strictest construction standard in the country, commonly cited around 175 mph wind ratings.
• Timeline: Commonly cited at 4–8 months for unincorporated Miami-Dade.
• Estimated cost: Construction commonly runs $150–$250 per sq ft in Miami-Dade, an 800 sq ft unit often lands around $120,000–$200,000 all-in.

Tampa ADU rules (2026)

• Status: Allowed, but Tampa's rules have a real geographic wrinkle. Traditional ADUs are permitted in designated neighborhoods, Seminole Heights and Tampa Heights among them.
• Size limit: Traditional ADUs in eligible neighborhoods commonly run up to roughly 900–950 sq ft or 50% of the primary dwelling.
• Lot size minimum: Commonly cited around 5,000 sq ft.
• Setbacks: Commonly cited around 3 ft for units under 750 sq ft.
• Owner-occupancy: Required. The City of Tampa's ADU program requires the main residence to be owner-occupied.
• Wind-load compliance: Tampa is not in the High-Velocity Hurricane Zone, but standard Florida Building Code wind provisions still apply.
• Timeline: Commonly cited around 60–120 days.
• Estimated cost: Construction commonly runs in the $140,000–$280,000 range for a detached unit.

Orlando ADU rules (2026)

• Status: Allowed in R-1, R-2, R-2A, and similar single-family residential zones under Chapter 58, Part 3A of Orlando's city code.
• Size limit: Commonly cited around 500 to 1,000 sq ft depending on lot size and which standard applies. Confirm the exact figure for your lot with Orlando City Planning.
• Lot size minimum: Commonly cited around 6,000 sq ft for most single-family districts.
• Setbacks: Commonly cited around 15 ft rear.
• Parking: One off-street space required.
• Owner-occupancy: Required, the owner must occupy either the primary residence or the ADU.
• Utilities: Independent water, sewer, and electric connections are generally required.
• Timeline: Commonly cited around 90–120 days.
• Estimated cost: Construction commonly runs $130,000–$260,000 for a detached unit.

Jacksonville ADU rules (2026)

• Status: Allowed by right in several residential zoning districts under Chapter 656 of the Jacksonville Ordinance Code.
• Size limit: Commonly cited at the lesser of 25% of the primary residence or 750 sq ft.
• Setbacks: Commonly cited around 20 ft rear.
• Parking: One off-street space required.
• Owner-occupancy: Required under the current ordinance.
• Wind-load compliance: Duval County is not in the High-Velocity Hurricane Zone, but standard Florida Building Code wind provisions still apply.
• Timeline: Commonly cited around 80–110 days.
• Estimated cost: Construction commonly runs $125,000–$245,000 for a detached unit.

Florida's hurricane and wind-load compliance: the real cost wild card

This is the piece of Florida ADU design that has nothing to do with any pending legislation and everything to do with the Florida Building Code, and it's the single biggest reason Florida ADU drawings cost more than a comparable set almost anywhere else in the country.

What it means in practice. Every ADU in Florida has to be engineered to withstand the wind loads specific to its location. That's not a vague statement, it shows up as concrete requirements in the drawings: impact-resistant windows and doors (or approved shutter systems as an alternative), reinforced roof-to-wall connections and hurricane straps, engineered structural connections throughout, and for masonry construction, proper foam closure at block cores.

Who has to show this in the drawings, and who has to stamp it. The drafter's job is to show the wind-resistant design clearly, connection details, product specifications, structural notes. Whether a structural engineer needs to stamp the calculations depends on the complexity of the design and, often, the specific wind zone.

What this does to cost. Hurricane-compliant drawings commonly run meaningfully more than a comparable non-Florida ADU design, this isn't a nice-to-have you can skip to save money, it's code. Budget for it as a real line item rather than a surprise.

Before you hire anyone

The real story here isn't a single law that changed everything overnight, it's a patchwork of city ordinances that keeps shifting, on top of a hurricane wind-load requirement that doesn't shift at all. Both pieces matter, and getting either one wrong costs real time and money.

Send us your address, city, and general project idea, and we'll tell you honestly whether an ADU is allowed on your property, what your local ordinance actually requires, and what hurricane compliance would add to your specific design and engineering cost. Start with ADU drafting services Florida. For the full ADU permit process across Florida, Texas, and North Carolina, see our ADU permit process guide.