ADUs are allowed in HelenaTypes:DetachedInternal
Types:DetachedInternal
Accessory Dwelling Unit (ADU) Rules for Helena, MT
Is your property eligible for an ADU?
# of Properties
1,072
Owner-occupied
20%
Zoning districts
35
Avg Home Value
$789,682
Median Lot Size
0.17 acres
Avg Income
$69,465
Residential Types:
1,072 housing units
Single Family
22%
Apts (4+ units)
76%
Other
2%
Zoning Districts:
12,043 parcels · 35 districts
R-2
43%(5,218)
R-3
18%(2,223)
B-2
6%(777)
R-1
6%(777)
Other
25%(3,048)
ADU Rules
What can you build in Helena, MT?
Helena, MT 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
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 Montana municipalities
Rules change at the town line. Check the municipality your property is actually in.
Lewis and Clark County