ADUs are allowed in ColumbiaTypes:DetachedInternal
Types:DetachedInternal
Accessory Dwelling Unit (ADU) Rules for Columbia, SC
Is your property eligible for an ADU?
# of Properties
85
Owner-occupied
45%
Zoning districts
41
Avg Home Value
$498,484
Median Lot Size
0.01 acres
Avg Income
$53,718
Residential Types:
85 housing units
Single Family
25%
Apts (4+ units)
2%
Condos
40%
Other
33%
Zoning Districts:
50,074 parcels · 41 districts
RSF-3
22%(10,881)
RSF-2
17%(8,637)
PD
11%(5,604)
RM-1
11%(5,470)
Other
39%(19,482)
ADU Rules
What can you build in Columbia, SC?
Columbia, SC 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 of 1,000 sq ft
- –Maximum size of 50% of the principal dwelling’s floor area (excluding carports, garages, and unfinished basements)
Detached ADU Size Limits
- –Maximum size is the lesser of 1,000 sq ft or 50% of the principal dwelling’s floor area, excluding carports, garages, and unfinished basements.
Max Units
- –1 ADU per lot for single-family detached (attached/internal or detached allowed); not allowed on duplex or multifamily.
Owner Occupancy
- –Owner must reside full-time in either the principal dwelling or ADU
Parking
- –1 off-street space per ADU (in addition to primary dwelling); must use the same driveway as the principal dwelling unless accessed from a different right-of-way (e.g., rear alley or separate street).
Rental Restrictions
- –Short-term rentals (<30 days) prohibited for ADUs (detached and attached)
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 South Carolina municipalities
Rules change at the town line. Check the municipality your property is actually in.
Richland County