ADU Rules in Florida: Can You Build a Guest House or Casita on Your Property?

One of the most common questions I hear from buyers exploring multigenerational living is whether they can legally build a guest house, casita, or accessory dwelling unit on their property. The answer in Florida has changed dramatically over the past two years, and the news is overwhelmingly positive for homeowners who want to add a separate living space for family members.

I'm John Belt with Keller Williams On The Water, and I work with families throughout the Bradenton-Sarasota area who are exploring multigenerational housing options. Understanding ADU regulations is a critical piece of that puzzle, so here is a comprehensive breakdown of where Florida law stands and what it means for you.

What Is an ADU

An accessory dwelling unit is a secondary residential unit located on the same lot as a primary single-family home. ADUs come in several forms. A detached ADU is a standalone structure, often called a guest house, casita, or granny flat, built in the backyard or side yard. An attached ADU is an addition built onto the existing home with its own entrance and living facilities. A converted ADU is an existing structure like a garage, bonus room, or pool house that has been renovated into a livable space with a bedroom, bathroom, and kitchen or kitchenette.

Regardless of the configuration, the defining characteristic is that an ADU is a complete, independent living space with sleeping, cooking, and sanitation facilities on a lot that already has a primary residence.

Florida Statewide ADU Law: What Changed in 2025

Florida took a major step forward for multigenerational housing when the state legislature passed legislation strengthening Florida Statutes Section 163.31771, effective July 1, 2025. The law established three critical protections for homeowners. First, cities and counties cannot ban ADUs in single-family residential zones. Second, local governments cannot cap the size of an ADU below 1,000 square feet. Third, municipalities cannot impose a blanket owner-occupancy requirement as a condition of approval.

This means that if you own a single-family home anywhere in Florida, your local government must allow you to build at least one ADU on your property. The practical impact has been enormous, particularly in areas like Manatee and Sarasota counties where multigenerational demand is high and lot sizes in many neighborhoods can accommodate a secondary structure.

What Local Governments Can Still Regulate

While the state law removed the most significant barriers, local governments retain authority over several aspects of ADU construction. Municipalities can still regulate setbacks, which determine how close the ADU can be to property lines and the primary structure. They can enforce design standards related to height, exterior materials, roofing, and architectural compatibility with the main home. Local building height limits still apply. Jurisdictions can restrict or prohibit short-term rentals in ADUs while still allowing long-term family use. Impact fees for water, sewer, and transportation connections remain within local authority.

In Manatee County specifically, the zoning code has been updated to comply with the state mandate. Homeowners should check with the Manatee County Building Department for the latest setback requirements and permit procedures. Sarasota County has similarly adopted the state framework, though the specific design standards differ from Manatee County.

HOA Restrictions: The Wild Card

Here is the critical caveat that many buyers overlook: private deed restrictions and HOA covenants are not preempted by Florida ADU statutes. If your homeowners association declaration prohibits accessory structures, detached buildings, or secondary residences, the state law does not override that restriction. Florida courts have consistently upheld properly recorded private deed restrictions over municipal zoning permissions.

This means that before you purchase a home with plans to build an ADU, you must review the community's declaration of covenants, conditions, and restrictions. If the documents prohibit accessory structures or secondary dwelling units, you will not be able to build an ADU regardless of what state and local zoning permits. Many newer master-planned communities in Lakewood Ranch and East Manatee County have restrictive covenants that limit or prohibit detached structures. Some older, unrestricted neighborhoods in West Bradenton and Palmetto may offer more flexibility.

SB 48: The 2026 Legislative Push

Florida lawmakers pushed even further in the 2026 legislative session with Senate Bill 48, which passed the Florida Senate with a unanimous 38-0 vote. The bill would have required every city and county to allow ADUs in all single-family residential zones by right, with no public hearing required, and would have further limited local regulatory barriers.

While SB 48 ultimately stalled in the Florida House on the final day of the session, the unanimous Senate support signals strong legislative momentum. Many observers expect similar legislation to pass in a future session, potentially further streamlining the process for homeowners who want to add an ADU.

Size, Costs, and Timeline for Building an ADU in Florida

Under current law, your ADU can be up to 1,000 square feet at minimum, and many jurisdictions allow larger units depending on lot size and zoning. A typical detached ADU with one bedroom, one bathroom, a kitchenette, and a small living area runs between $150,000 and $300,000 to build from the ground up in the Bradenton-Sarasota market, depending on finishes and site conditions.

Permit timelines in Manatee County generally range from four to twelve weeks for plan review, with construction taking an additional four to eight months for a detached unit. Attached ADUs and garage conversions typically move faster since they leverage the existing structure and utility connections.

How This Affects Your Home Search

If you are shopping for a multigenerational home in the Bradenton-Sarasota area, understanding ADU rules expands your options significantly. You are no longer limited to homes that already have an in-law suite built in. Any single-family home on an adequately sized lot in an unrestricted neighborhood becomes a candidate for multigenerational living, because you can add the separate living space after closing.

This is where working with a local Realtor who understands both the real estate market and the regulatory landscape makes a real difference. I help buyers identify properties with ADU potential, navigate the permit process, and connect with builders who specialize in accessory dwelling units.

If you are considering building an ADU or buying a home with multigenerational potential in Manatee County, reach out to me, John Belt, at Keller Williams On The Water. I will help you understand your options and find the right property for your family.