

ADUs are allowed in St AugustineTypes:DetachedInternal
Types:DetachedInternal
Accessory Dwelling Unit (ADU) Rules for St Augustine, FL
Is your property eligible for an ADU?
# of Properties
11,154
Owner-occupied
54%
Zoning districts
28
Avg Home Value
$646,679
Median Lot Size
0.21 acres
Avg Income
$99,789
Residential Types:
11,154 housing units
Single Family
66%
Apts (4+ units)
9%
Other
25%
Zoning Districts:
16,399 parcels · 28 districts
RS-2
27%(4,407)
RS-1
13%(2,082)
RG-1
12%(2,049)
CM-2
9%(1,503)
Other
39%(6,358)
ADU Rules
What can you build in St Augustine, FL?
St Augustine, 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 size of 800 sq ft or 25% of the primary dwelling unit’s floor area, whichever is less.
Detached ADU Size Limits
- –Maximum size of 800 sq ft or 25% of the primary dwelling unit, whichever is less
Owner Occupancy
- –ADU allowed only in owner-occupied premises with ≤3 units.
Parking
- –No explicit min/max; HP Districts 1–4: no ADU parking; unlisted uses follow closest listed use; parking typically on-site with joint/off-site spaces within 400 ft by exception.
Rental Restrictions
- –RS-1/RS-2: nightly short-term rentals prohibited; only weekly-or-longer stays with registration; HP-1: minimum rental term monthly-or-longer
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.
St. Johns County