ADU Zoning in Alachua County, Florida (2026)
What ADU can you build in your Alachua County backyard?
Instant zoning report — see exactly what your zoning allows: permitted ADU types, size limits, setbacks, and lot requirements for your specific property.
Alachua County ADU — Key Facts
- Alachua County allows one ADU in A, RE, RE-1 and R-1 districts (ULDC Section 404.24)
- Size: the greater of 1,700 sq ft or 50% of the main home's living area
- The owner must live on the property, with homestead exemption as proof
- The ADU uses the main home's driveway and, in most cases, its water, sewer, septic or well
- ADUs do not count toward density
- Rural/agriculture lots need 5 acres, or 1 acre with limited wastewater flow
Unincorporated Alachua County Rules
*These rules apply if your address is NOT inside a specific city limit.
Alachua County ADU Permit Process
- 1Confirm the parcel is in unincorporated Alachua County, not one of its nine municipalities.
- 2Confirm A, RE, RE-1, R-1aa, R-1a, R-1b or R-1c zoning and the land use designation.
- 3Show proof of homestead exemption (or an owner-residency affidavit).
- 4Plan to connect to the main home's water and sewer, or septic and well, with Florida Department of Health approval where applicable.
- 5Apply for a building permit with Alachua County Growth Management.
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Cities in Alachua County
Alachua County ADU — Frequently Asked Questions
The most common questions from Alachua County homeowners about ADU rules, permits, and costs.
How big can an ADU be in unincorporated Alachua County?
The living area can be up to 50% of the main home or 1,700 sq ft, whichever is greater (ULDC Section 404.24). So any qualifying home can have an ADU of up to 1,700 sq ft, and a home over 3,400 sq ft can have a larger one.
Do I have to live on the property to build an ADU in Alachua County?
Yes. The owner must live in either the main home or the ADU. In existing neighborhoods you show proof of homestead exemption before the permit is issued; if both units are permitted together you submit an affidavit that you will live there.
Does an Alachua County ADU need its own utilities?
No. Unless the lot is in the A district with a rural/agriculture land use designation, it cannot have separate ones. It connects to the main home's central water and sewer where available, or to its septic system and well, meeting Florida Department of Health requirements.
Can I build an ADU on rural land in Alachua County?
In the rural/agriculture land use category the lot must be at least 5 acres, or as small as 1 acre if the two units' combined wastewater flow is no more than 700 gallons per day, with at least one buildable acre outside regulated conservation areas.
Do Alachua County's rules apply in Gainesville?
No. These rules cover unincorporated Alachua County. Gainesville and the other eight municipalities (Alachua, Archer, Hawthorne, High Springs, La Crosse, Micanopy, Newberry and Waldo) set their own rules.
Florida ADU Laws 2026 — What State Law Does and Doesn't Do
How §163.31771 works, and what your local government controls.
Find out what ADU you can build in your backyard
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