ADUs are allowed in Key WestTypes:DetachedInternal
Types:DetachedInternal
Accessory Dwelling Unit (ADU) Rules for Key West, FL
Is your property eligible for an ADU?
# of Properties
8,201
Owner-occupied
53%
Zoning districts
46
Avg Home Value
$1,114,980
Median Lot Size
0.06 acres
Avg Income
$101,917
Residential Types:
8,201 housing units
Single Family
68%
Apts (4+ units)
26%
Other
7%
Zoning Districts:
14,830 parcels · 46 districts
SF
19%(2,745)
HMDR
17%(2,520)
MDR-C
8%(1,189)
HHDR
7%(1,038)
Other
49%(7,338)
ADU Rules
What can you build in Key West, FL?
Key West, FL follows state and local rules for Accessory Dwelling Units. Here is a concise overview of the local rules.
Eligibility
- –Internal / Attached ADU: By Right
- –Detached ADU: By Right
Interior / Attached ADU Size Limits
- –Maximum 600 sq ft for an internal or attached accessory dwelling unit in the Single-Family (SF) district; no variance can increase this cap.
Detached ADU Size Limits
- –Maximum detached ADU size of 600 sq ft in the Single-Family Residential district
Max Units
- –1 ADU per principal dwelling unit per lot (SF, attached or detached)
Parking
- –0 spaces/ADU; SF district has no additional parking for accessory units; in mixed-use districts, accessory unit infill may substitute with two bicycle/scooter spaces per unit
Rental Restrictions
- –Short-term/transient rentals prohibited.
- –If rented, rent capped at 25% of the monthly median household income; perpetual deed restriction and workforce housing income limits apply.
- –Accessory units restricted to occupancy by permanent residents.
ADU State Law
What can you build in Florida?
- –Florida does not have a statewide ADU mandate. There is no state-level requirement for cities or counties to allow ADUs.
- –ADUs in Florida are regulated entirely at the local level. Some jurisdictions allow ADUs broadly, others allow them with strict conditions, and some prohibit them altogether.
- –Florida Statute 163.31771 is optional. It allows local governments to adopt ADU ordinances for affordable housing, but it does not require any jurisdiction to allow ADUs, and local governments may adopt ADU rules outside of this statute.
- –County and city rules may differ. In unincorporated areas, county zoning controls whether ADUs are allowed; within city limits, municipal zoning codes apply.
What's allowed on your lot?
These are the municipality-wide rules. What's allowed on a specific property also depends on state laws, setbacks, floor area ratio, lot coverage, environmental constraints, topography, and other property-specific factors. Search your address on FutureLot to see what's allowed on your property.
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ADU rules in other Florida municipalities
Rules change at the town line. Check the municipality your property is actually in.
Monroe County