ADUs are allowed in LewistonTypes:DetachedInternal
Types:DetachedInternal
Accessory Dwelling Unit (ADU) Rules for Lewiston, ID
Is your property eligible for an ADU?
# of Parcels
15,467
Zoning districts
25
Avg Parcel Value
$360,537
Zoning Districts:
15,467 parcels · 25 districts
R2A
25%(3,818)
R2
16%(2,507)
R1
15%(2,307)
PD
8%(1,204)
Other
36%(5,631)
ADU Rules
What can you build in Lewiston, ID?
Lewiston, ID 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
Detached ADU Size Limits
- –Normal Hill North: Max detached accessory building area is the greater of 60% of the dwelling’s habitable floor area or 720 sq ft, but never more than 1,440 sq ft.
- –Normal Hill South: Max detached accessory building area is the greater of 70% of the dwelling’s habitable floor area or 1,200 sq ft, but never more than 2,400 sq ft.
Owner Occupancy
- –Owner-occupancy not required; ADU and primary dwelling must share ownership.
Parking
- –1 space per bedroom; max none; up to 0.5 of adjacent on-street parking may be counted toward required off-street parking.
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.
Check my propertyHow can we help you?
Get matched with trusted local builders
Understand what's allowed on your property
Learn the key rules and size limits for ADUs