Miami-Dade County Zoning
ADU Rules for
Miami, Florida
Miami allows ADUs to fight the affordability crisis. Ideal for garage conversions or small concrete casitas.
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Updated for 2026
Zoning Code
Miami 21 Code
Local ordinance code.
Max Unit Size
450 - 800 sq ft
Living area allowed.
Setbacks
5ft Rear / 5ft Side
Req. distance from lines.
Important Local Restriction
Septic tanks are the #1 killer of deals here. You likely need to connect to sewer, which is expensive.
Common Questions in Miami
Answers based on the Miami 21 Code zoning text and local building department data.
How much does it cost to build an ADU in Miami?
While costs vary by finish level, the average permitted value for accessory structures in Miami is currently around $2,500. Prefab modular units may be cheaper, while custom concrete block construction will be higher.
What is the maximum size for a guest house in Miami?
Under the Miami 21 Code zoning ordinance, detached units are typically limited to 450 - 800 sq ft. However, state law SB-48 may allow for larger units if they meet specific setback requirements.
What are the setback rules for Miami?
You generally need to maintain a distance of 5ft Rear / 5ft Side from your property lines. Corner lots and historic districts may have stricter overlays.
Can I rent out my ADU in Miami?
Yes. Rental demand in Miami is rated as 'Extreme'. While long-term rentals are allowed by right, short-term rentals (Airbnb) may require a separate license depending on your specific neighborhood zoning.
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