ADUs are allowed in Unincorporated SumnerTypes:DetachedInternal
Types:DetachedInternal
Accessory Dwelling Unit (ADU) Rules for Unincorporated Sumner, TN
Is your property eligible for an ADU?
# of Properties
23,062
Owner-occupied
65%
Zoning districts
35
Avg Home Value
$427,851
Median Lot Size
1.66 acres
Avg Income
$97,646
Residential Types:
23,062 housing units
Residential
100%
Zoning Districts:
29,017 parcels · 35 districts
RP
52%(15,190)
RR
40%(11,655)
PUD
5%(1,564)
SR
1%(168)
Other
2%(440)
ADU Rules
What can you build in Unincorporated Sumner, TN?
Unincorporated Sumner, TN 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 is the greater of 300 sq ft or 25% of the principal dwelling’s gross floor area (excluding garage/utility).
Detached ADU Size Limits
- –Maximum size under accessory-structure limits: 2,000 sq ft on lots up to 40,000 sq ft; otherwise 5% of lot area (shared with all accessory structures).
- –Maximum size may not exceed the principal dwelling’s size.
Max Units
- –1 ADU per single-family lot
- –0 ADUs per lot (duplex)
- –0 ADUs per lot (multifamily)
Owner Occupancy
- –Owner must reside in either the principal structure or the ADU.
Parking
- –No numeric ADU parking min/max; ADUs require additional off-street parking beyond the primary dwelling; Planning Director determines standards for unlisted uses and may prohibit a separate ADU driveway unless lot-specific conditions justify
Rental Restrictions
- –ADUs may not be rented or leased; both short-term and long-term rentals are prohibited.
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 Tennessee municipalities
Rules change at the town line. Check the municipality your property is actually in.
Sumner County