ADUs are allowed in Island CityTypes:DetachedInternal
Types:DetachedInternal
Accessory Dwelling Unit (ADU) Rules for Island City, OR
Is your property eligible for an ADU?
# of Properties
378
Owner-occupied
77%
Zoning districts
10
Avg Home Value
$345,436
Median Lot Size
0.24 acres
Avg Income
$62,780
Residential Types:
378 housing units
Single Family
50%
Apts (4+ units)
16%
Other
34%
Zoning Districts:
634 parcels · 10 districts
R-1
65%(411)
C-1
20%(128)
R-E
10%(66)
BP
1%(8)
Other
3%(21)
ADU Rules
What can you build in Island City, OR?
Island City, OR 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
- –In R-1, R-2, and R-E zones, the internal ADU may be up to 50% of the primary dwelling’s habitable floor area.
Detached ADU Size Limits
- –Maximum ADU size is 50% of the habitable floor area of the primary dwelling (applies in R-1, R-2, and R-E).
Parking
- –2 spaces/ADU; no max; City may adjust up/down via similar uses or traffic study; Title 13 adjustments may allow on-street parking; off-street spaces may not be in required yards/setbacks unless authorized
ADU State Law
What can you build in Oregon?
- –In urban growth areas, Oregon law requires cities and counties to allow at least one ADU on lots zoned for detached single-family homes.
- –Local jurisdictions cannot require owner occupancy for ADUs, but may regulate short-term or vacation rentals.
- –There are no statewide limits on ADU size, height, setbacks, lot size, or floor area ratio. Local zoning rules apply.
- –Parking requirements, if any, are set by the local jurisdiction, subject to state limitations.
- –Some cities may allow more than one ADU per lot, depending on local code.
- –Oregon law does not require counties to allow ADUs in rural residential zones. Whether an ADU is allowed depends on county zoning.
- –ADUs in rural residential areas cannot be used for short-term or vacation rentals.
- –Additional requirements may apply related to wildfire risk, water supply, septic capacity, and fire access.
- –Counties may impose additional restrictions beyond state law or choose not to allow ADUs at all.
- –If a county allows ADUs, state law imposes strict limits, including a minimum 2-acre lot size, a maximum ADU size of 900 sq ft, a location within 100 ft of the primary dwelling, and a limit of one ADU per parcel.
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 Oregon municipalities
Rules change at the town line. Check the municipality your property is actually in.
Union County