ADUs are allowed in JamestownTypes:DetachedInternal
Types:DetachedInternal
Accessory Dwelling Unit (ADU) Rules for Jamestown, RI
Is your property eligible for an ADU?
# of Properties
2,777
Owner-occupied
100%
Zoning districts
12
Median Lot Size
0.41 acres
Avg Income
$135,577
Residential Types:
2,777 housing units
Single Family
99%
Apts (4+ units)
1%
Zoning Districts:
3,718 parcels · 12 districts
R-40
41%(1,525)
RR-800
24%(886)
R-20
15%(552)
R-8
11%(397)
Other
10%(358)
ADU Rules
What can you build in Jamestown, RI?
Jamestown, RI 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: 900 sq ft or 60% of the principal dwelling’s floor area for a studio/1-bedroom, and 1,200 sq ft or 60% for a 2-bedroom (whichever is less).
Detached ADU Size Limits
- –Maximum detached ADU size is the lesser of 60% of the principal dwelling’s floor area and: 900 sq ft for a studio/one-bedroom or 1,200 sq ft for a two-bedroom.
Max Units
- –1 ADU per lot for single-family and duplex by right.
- –0 ADUs per lot for multifamily lots.
- –Total maximum remains 1 ADU per lot by right; no separate JADU category.
Owner Occupancy
- –Owner-occupancy required unless both units are leased long-term
Parking
- –1 off-street parking space per ADU, in addition to the primary dwelling's required spaces; no maximum; no ADU-specific waivers (e.g., transit proximity).
Rental Restrictions
- –Short-term rentals prohibited for ADUs.
- –If rented, ADU must be long-term (≥1 year).
- –If neither unit is owner-occupied, both units must be rented long-term; if the ADU is owner-occupied, the principal dwelling may only be rented long-term (≥1 year).
ADU State Law
What can you build in Rhode Island?
- –On an owner-occupied property as a reasonable accommodation for family members with disabilities;
- –On a lot with a total lot area of twenty thousand square feet (20,000 sq. ft.) or more for which the primary use is residential;
- –Where the proposed ADU is located within the existing footprint of the primary structure or existing accessory attached or detached structure and does not expand the footprint of the structure.
- –Subject to applicable dimensional requirements of the municipality
- –As per §45-24-38 of the RI Zoning Enabling Act, if an existing lot is smaller than the minimum lot size required by zoning, its setback requirements are reduced in proportion to the lot's size, and its maximum lot coverage is increased by the inverse proportion.
- –One ADU per lot
- –No short term rentals
- –Studio or 1 bedroom ADU may be up to 900 sq ft or 60% of the Gross Floor Area of the principal dwelling, whichever is less
- –2 bedroom ADU may be up to 1200 sq ft or 60% of the Gross Floor Area of the principal dwelling, whichever is less
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 Rhode Island municipalities
Rules change at the town line. Check the municipality your property is actually in.
Newport County