ADUs are allowed in Grand JunctionTypes:DetachedInternal
Types:DetachedInternal
Accessory Dwelling Unit (ADU) Rules for Grand Junction, CO
Is your property eligible for an ADU?
# of Properties
30,147
Owner-occupied
70%
Zoning districts
30
Avg Home Value
$407,406
Median Lot Size
0.18 acres
Avg Income
$80,922
Residential Types:
30,147 housing units
Single Family
8%
Apts (4+ units)
1%
Other
90%
Zoning Districts:
35,838 parcels · 30 districts
PD
25%(8,840)
RM-8
23%(8,414)
RL-4
12%(4,235)
RL-5
12%(4,172)
Other
28%(10,177)
ADU Rules
What can you build in Grand Junction, CO?
Grand Junction, CO 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 900 sq ft of habitable space for an internal/attached ADU
Detached ADU Size Limits
- –Maximum 900 sq ft of habitable space for a detached ADU.
Max Units
- –Single-unit detached: up to 2 ADUs per lot (at least one attached). Single-unit attached: up to 2 ADUs per lot (at least one attached). Duplex: 1 ADU per lot. Multi-unit: 0 ADUs. Cottage court: 0 ADUs.
Parking
- –No ADU parking ratio; unlisted uses determined by Director per § 21.08.010(b)(2).
Rental Restrictions
- –Short-term rentals under 30 days require a city STR permit with area-wide and per-building caps (max 2 STRs in a 4-unit building, only one primary), plus occupancy/parking and annual renewal. Long-term rentals have no explicit restrictions.
ADU State Law
What can you build in Colorado?
- –ADUs must be approved based on objective standards; no discretionary hearings allowed.
- –Historic properties: Local historic review may still apply in designated historic districts.
- –Exempt parcels: ADUs are not required to be allowed on parcels without adequate water/sewer, in floodways, or on certain historic properties.
- –HOAs cannot prohibit ADUs: HOA rules that conflict with the state ADU law are void.
- –Parking exceptions exist: In rare cases, one parking space may be required if there is no existing off-street parking and on-street parking is prohibited.
- –Local rules still matter: Building code, fire code, utility capacity, and life-safety standards still apply.
- –More permissive is allowed: Municipalities may allow larger ADUs, multiple ADUs, or additional housing types beyond what the state requires.
- –Local zoning controls whether ADUs are allowed at all.
- –HOA rules may still apply.
- –More permissive local rules are allowed.
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 Colorado municipalities
Rules change at the town line. Check the municipality your property is actually in.
Mesa County