ADUs are allowed in Crystal LakeTypes:Internal
Types:Internal
Accessory Dwelling Unit (ADU) Rules for Crystal Lake, IL
Is your property eligible for an ADU?
# of Properties
887
Owner-occupied
29%
Zoning districts
36
Avg Home Value
$82,193
Median Lot Size
0.18 acres
Avg Income
$119,649
Residential Types:
887 housing units
Single Family
2%
Apts (4+ units)
94%
Other
3%
Zoning Districts:
16,386 parcels · 36 districts
R-2
37%(6,048)
R-1/PUD
15%(2,467)
R-3B/PUD
10%(1,664)
R-1
8%(1,379)
Other
29%(4,828)
ADU Rules
What can you build in Crystal Lake, IL?
Crystal Lake, 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: Not permitted
Interior / Attached ADU Size Limits
- –Maximum internal ADU size of 800 sq ft
- –Internal ADU size cannot exceed the principal structure’s gross building area
Max Units
- –1 ADU per lot; total 2 dwelling units (1 principal + 1 ADU).
- –0 ADUs per lot on lots with two-family or multifamily principal structures.
Parking
- –No ADU-specific min/max; unlisted uses parking set per PAS 510/511 or City Engineer; Zoning Administrator may grant up to 10% reduction; reductions in Downtown District and Virginia Street Corridor Overlay; citywide parking maximums: 125% of minimum for lots <200 spaces, 115% for 200+ spaces.
Rental Restrictions
- –Accessory structures cannot be used for overnight lodging or as a tourist home.
- –ADUs may not be used for tourist homes; no tourist home may be rented for less than 24 hours.
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.
McHenry County