ADUs are allowed in BallwinTypes:DetachedInternal
Types:DetachedInternal
Accessory Dwelling Unit (ADU) Rules for Ballwin, MO
Is your property eligible for an ADU?
# of Properties
11,131
Owner-occupied
90%
Zoning districts
23
Avg Home Value
$400,538
Median Lot Size
0.29 acres
Avg Income
$127,975
Residential Types:
11,134 housing units
Single Family
93%
Apts (4+ units)
7%
Zoning Districts:
11,768 parcels · 23 districts
R-2
40%(4,745)
R-3
32%(3,816)
R-1
11%(1,353)
R-4
7%(789)
Other
9%(1,065)
ADU Rules
What can you build in Ballwin, MO?
Ballwin, MO follows state and local rules for Accessory Dwelling Units. Here is a concise overview of the local rules.
Eligibility
- –Internal / Attached ADU: Special Permit
- –Detached ADU: Special Permit
Max Units
- –0 per lot in single-family districts (ADUs prohibited).
- –Articles IX–XII: ADUs allowed by special use; none specified as to max per lot.
Parking
- –1 space/ADU (1.5 for two-family/multi); on-site only; secondary ADUs require a special use; off-site parking allowed only for nonresidential; not applicable in C-2/C-3.
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 Missouri municipalities
Rules change at the town line. Check the municipality your property is actually in.
St. Louis County