ADUs are allowed in Unincorporated WashingtonTypes:DetachedInternal
Types:DetachedInternal
Accessory Dwelling Unit (ADU) Rules for Unincorporated Washington, TN
Is your property eligible for an ADU?
# of Properties
22,756
Owner-occupied
62%
Zoning districts
25
Avg Home Value
$249,462
Median Lot Size
0.74 acres
Avg Income
$70,748
Residential Types:
22,756 housing units
Household Units
100%
Zoning Districts:
32,013 parcels · 25 districts
A-1
51%(16,410)
R-1
33%(10,578)
R-3
5%(1,576)
B-3
2%(571)
Other
9%(2,878)
ADU Rules
What can you build in Unincorporated Washington, TN?
Unincorporated Washington, TN follows state and local rules for Accessory Dwelling Units. Here is a concise overview of the local rules.
Eligibility
- –Internal / Attached ADU: Conditional Use Permit
- –Detached ADU: Conditional Use Permit
Parking
- –2 spaces/ADU; max 3 spaces (garage spaces not counted toward max); garage spaces and driveways may count toward required (1 garage bay = 1 space; 18' driveway = 1 space if not blocking walkway); off-premises parking allowed within 400 ft by Special Exception; Planning Commission waiver may exceed max; excess spaces/aisles must use durable pervious material.
Rental Restrictions
- –ADU rental prohibited; cannot be used for income (no short-term or long-term rentals)
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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