ADUs are allowed in Rock IslandTypes:Detached
Types:Detached
Accessory Dwelling Unit (ADU) Rules for Rock Island, IL
Is your property eligible for an ADU?
# of Parcels
15,757
Zoning districts
25
Avg Parcel Value
$54,731
Median Parcel Size
0.17 acres
Zoning Districts:
15,625 parcels · 25 districts
R2
41%(6,361)
R1
39%(6,147)
PUD
4%(569)
B3
3%(492)
Other
13%(2,056)
ADU Rules
What can you build in Rock Island, IL?
Rock Island, IL follows state and local rules for Accessory Dwelling Units. Here is a concise overview of the local rules.
Eligibility
- –Internal / Attached ADU: Not permitted
- –Detached ADU: By Right
Detached ADU Size Limits
- –Maximum size of 400 sq ft for a detached accessory dwelling unit
Max Units
- –1 ADU per lot
Owner Occupancy
- –One of the two dwelling units must be owner-occupied
Parking
- –3 total spaces required (2 for the principal dwelling + 1 per ADU); maximum 3; principal parking must be maintained; detached garage conversions allowed only if minimum spaces are maintained on-site.
Rental Restrictions
- –One of the two dwelling units must be owner-occupied; you cannot rent both the principal dwelling and the detached ADU. Short-term rentals (<30 days) are allowed only with a city STR license and compliance with standards (parking: at least one off-street space per STR; operator must reside in Rock Island or within 10 miles; signage limited to 1 sq ft; inspections, annual renewal; licenses may be revoked).
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 Illinois municipalities
Rules change at the town line. Check the municipality your property is actually in.
Rock Island County