ADUs are allowed in Iowa CityTypes:DetachedInternal
Types:DetachedInternal
Accessory Dwelling Unit (ADU) Rules for Iowa City, IA
Is your property eligible for an ADU?
# of Properties
25,312
Owner-occupied
57%
Zoning districts
75
Avg Home Value
$317,433
Median Lot Size
0.28 acres
Avg Income
$76,105
Residential Types:
25,312 housing units
Single Family
2%
Other
98%
Zoning Districts:
27,381 parcels · 75 districts
RS5
35%(9,566)
OPD8
7%(1,960)
OPD5
7%(1,910)
RM12
6%(1,653)
Other
45%(12,292)
ADU Rules
What can you build in Iowa City, IA?
Iowa City, IA 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 of 1,000 sq ft or 50% of the principal dwelling’s floor area (excluding any attached garage), whichever is less.
Detached ADU Size Limits
- –Maximum 1,000 sq ft or 50% of the total floor area of the principal use (excluding the attached garage), whichever is less.
Max Units
- –1 ADU per lot for single-family or two-family lots
- –0 ADUs per lot for multifamily (3+ principal units)
- –1 detached ADU per lot/design site in Form-Based Zones (carriage house: 1 unit per building; 1 building per design site)
Owner Occupancy
- –Owner must occupy a unit on premises; ADU and principal share ownership.
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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Is your property eligible for an ADU?
ADU rules in other Iowa municipalities
Rules change at the town line. Check the municipality your property is actually in.
Johnson County