ADUs are allowed in UnionTypes:DetachedInternal
Types:DetachedInternal
Accessory Dwelling Unit (ADU) Rules for Union, MO
Is your property eligible for an ADU?
# of Parcels
5,434
Zoning districts
13
Zoning Districts:
5,438 parcels · 13 districts
R-2
42%(2,302)
R-3
18%(952)
R-1
14%(774)
B-2
14%(743)
Other
12%(667)
ADU Rules
What can you build in Union, MO?
Union, MO 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 internal or attached in-home apartment size of 500 sq ft.
- –Maximum internal or attached in-home apartment size of 50% of the principal dwelling’s floor area.
Detached ADU Size Limits
- –Maximum size of 500 sq ft for a detached accessory dwelling
- –Maximum size of 50% of the principal dwelling’s size for a detached accessory dwelling
Owner Occupancy
- –No owner-occupancy requirement
Parking
- –1 off-street space per ADU (on the lot); applies only to medical hardship ADUs; space must be in a side or rear yard; one ADU per lot
Rental Restrictions
- –Renting of ADUs is prohibited; accessory dwellings shall not be rented or sold separately from the sale of the entire lot, including the principal dwelling unit.
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.
Franklin County