ADUs Are Having a Moment in Florida
Accessory dwelling units, or ADUs, have been around for a long time. But recent changes to Florida law have made them a much more realistic option for homeowners across the state. Whether you want to build a guest house for aging parents, create a rental unit for extra income, or just add a detached home office, ADUs are worth a serious look.
What Counts as an ADU?
An ADU is a secondary dwelling unit on a single-family residential lot. It can be:
- A detached structure (standalone guest house or cottage)
- An attached addition to the main house with its own entrance
- A garage conversion turned into a living space
- A converted space above an existing garage
To qualify as a true ADU, it needs its own kitchen, bathroom, sleeping area, and separate entrance. It's basically a small, independent home on the same lot as your primary residence.
Florida's New ADU Laws
Florida passed legislation (SB 102, effective July 2023) that preempts local governments from outright banning ADUs on single-family residential lots. That's a big deal because many cities and counties previously made it nearly impossible to build one.
What the law does:
- Requires local governments to allow ADUs on lots zoned for single-family residential use
- Prohibits local governments from requiring the owner to live in either the primary home or the ADU (this was a big barrier before)
- Allows ADUs to be used as rental units
- Still allows local governments to set reasonable standards for size, setbacks, parking, and design
What the law doesn't do:
- It doesn't override HOA restrictions. If your HOA covenants prohibit ADUs or accessory structures, the state law doesn't help you.
- It doesn't waive permitting requirements. You still need to go through the full permit process.
What It Costs to Build an ADU in Central Florida
ADU costs depend heavily on size, finishes, and whether you're building from scratch or converting existing space.
- Garage conversion: $30,000 to $60,000. You're working with an existing structure, so costs are lower. Adding plumbing for a kitchen and bath is the biggest expense.
- Detached ADU (400 to 600 sq ft): $80,000 to $150,000. This is a ground-up build with its own foundation, utilities, and everything.
- Detached ADU (600 to 1,000 sq ft): $120,000 to $200,000+. A larger unit with a full kitchen, bedroom, bathroom, and living area.
- Above-garage unit: $60,000 to $120,000. The structure already exists, but you're adding living space with plumbing, electrical, and HVAC.
The Permitting Process
Building an ADU in Orange County, Seminole County, or anywhere else in Central Florida requires permits. The process looks similar to any new construction:
- Check local zoning to confirm ADU eligibility on your lot and learn about size and setback restrictions
- Hire an architect or designer to draw up plans that meet the Florida Building Code
- Submit plans to the county building department for review
- Address reviewer comments and get approval
- Pull your permits and begin construction
- Schedule inspections at each phase, just like a regular build
- Receive your Certificate of Occupancy when the unit is complete
Plan for 4 to 8 weeks for the permitting phase, depending on the county.
Design Considerations
A few things to think about as you plan:
- Parking. Some municipalities require an additional parking space for the ADU. Check your local requirements.
- Utility connections. You can tap into the main house's utilities or run separate meters. Separate meters make it easier if you're renting the unit out.
- Privacy. Placement on the lot matters. You want both the main house and the ADU to feel like they have their own space.
- Style. Most local regulations require the ADU to be architecturally consistent with the main house. It doesn't have to match exactly, but it shouldn't look out of place.
Rental Income Potential
An ADU in the Orlando metro area can bring in real money:
- A well-finished 1-bed, 1-bath ADU in a decent location can rent for $1,200 to $1,800 per month on a standard lease
- Short-term rental income through platforms like Airbnb or Vrbo can be higher, but check local short-term rental regulations first. Orange County and several municipalities have specific rules about this.
- Even at $1,400 per month in rent, you're looking at $16,800 per year in income. That's a solid return on your investment.
J&N StructureWorks builds ADUs and guest houses across Central Florida. We handle everything from design and permitting through construction and final inspection. If you're thinking about adding an ADU to your property, we can walk you through the options and the numbers.