ADUs are allowed in GrayslakeTypes:DetachedInternal
Types:DetachedInternal
Accessory Dwelling Unit (ADU) Rules for Grayslake, IL
Is your property eligible for an ADU?
# of Properties
7,060
Owner-occupied
92%
Zoning districts
29
Avg Home Value
$110,383
Median Lot Size
0.19 acres
Avg Income
$123,966
Residential Types:
7,060 housing units
Residential Improvements
100%
Zoning Districts:
8,745 parcels · 29 districts
PUD
52%(4,512)
R3
17%(1,495)
R3B
6%(496)
R3A
4%(353)
Other
22%(1,889)
ADU Rules
What can you build in Grayslake, IL?
Grayslake, IL 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 for an accessory residence (internal or attached ADU).
Detached ADU Size Limits
- –Maximum size of 1,000 sq ft for a detached accessory residence
- –Maximum size of 40% of the principal building’s floor area
Parking
- –No ADU-specific min/max; CB District accessory units: 1 space per efficiency/1-bedroom and 2 spaces per 2+ bedrooms; general residential rates apply to other dwellings.
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 Illinois municipalities
Rules change at the town line. Check the municipality your property is actually in.
Lake County