ADU rules for Unincorporated St. Clair

Accessory Dwelling Unit (ADU) Rules for Unincorporated St. Clair, IL

Is your property eligible for an ADU?

# of Properties

20,442

Owner-occupied

67%

Zoning districts

Avg Home Value

$60,389

Median Lot Size

0.41 acres

Avg Income

$91,377

Residential Types:

20,442 housing units

Single Family

18%

Other

82%

Zoning Districts:

30,898 parcels · 58 districts

40%(12,288)

SR3

25%(7,807)

SRMH

8%(2,376)

RR3

8%(2,349)

Other

20%(6,078)

ADU Rules

What can you build in Unincorporated St. Clair, IL?

Unincorporated St. Clair, IL follows state and local rules for Accessory Dwelling Units. Here is a concise overview of the local rules.

Eligibility

–Internal / Attached ADU: Not addressed in the local bylaw
–Detached ADU: Not addressed in the local bylaw

Max Units

–0 per lot (prohibited) countywide
–1 per lot in the A Agricultural Industry District (farm residence as an accessory dwelling)

Owner Occupancy

–No owner-occupancy requirement for ADUs.

Rental Restrictions

–Detached ADU use as a dwelling is prohibited; cannot be rented (only a single-family dwelling permitted under the A Agricultural Industry District standards).

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 Illinois municipalities

Rules change at the town line. Check the municipality your property is actually in.

St. Clair County

Belleville Collinsville East St Louis Ofallon

See all municipalities in St. Clair County →See all Illinois municipalities →