ADU rules for Decatur
Accessory Dwelling Unit (ADU) Rules for Decatur, IL
Is your property eligible for an ADU?
# of Properties
357
Owner-occupied
28%
Zoning districts
29
Median Lot Size
0.89 acres
Avg Income
$45,370
Residential Types:
357 housing units
Vacant Residential Lot
100%
Zoning Districts:
35,044 parcels · 29 districts
R3
58%(20,161)
R1
12%(4,111)
R5
7%(2,555)
R6
6%(2,264)
Other
17%(5,953)
ADU Rules
What can you build in Decatur, IL?
Decatur, 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
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.
Macon County