ADUs are allowed in BasaltTypes:DetachedInternal
Types:DetachedInternal
Accessory Dwelling Unit (ADU) Rules for Basalt, CO
Is your property eligible for an ADU?
# of Properties
2,283
Owner-occupied
36%
Zoning districts
20
Avg Home Value
$1,536,523
Median Lot Size
0.17 acres
Avg Income
$104,364
Residential Types:
2,283 housing units
Single Family
60%
Apts (4+ units)
1%
Other
39%
Zoning Districts:
2,991 parcels · 20 districts
R4
27%(810)
C3
24%(719)
R3
15%(457)
C2
8%(238)
Other
26%(767)
ADU Rules
What can you build in Basalt, CO?
Basalt, 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 500 sq ft in R-4 MD district
- –Town-wide maximum dwelling unit size of 5,000 sq ft (applies to all ADUs)
- –Maximum size of 1,000 sq ft in R-3 Traditional Neighborhood/Hill
Detached ADU Size Limits
- –R-4 MD (single-family): Maximum detached ADU size of 500 sq ft
- –R-3 TN: Maximum detached ADU size of 1,000 sq ft
Max Units
- –Single-family: 1 ADU per lot
- –Duplex & multifamily: none specified
Owner Occupancy
- –One unit must be resident-occupied as a primary residence.
Parking
- –Min: 1.5 spaces (efficiency/1BR); 2 for 2BR; 2 for 3BR; 3 for 4+BR. Max: none stated. Exception: +0.25 guest space per unit for multi-family or mobile home parks with 3+ units.
Rental Restrictions
- –STRs limited to one entity or party at any one time for detached/attached ADU and the main dwelling; cannot short-term rent to separate groups.
- –R-4 MD district: units are not permitted to be short-term rental units, including ADUs.
- –Deed-restricted ADUs: occupancy/rental limited to households meeting Community Housing Guidelines.
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.
Check my propertyHow can we help you?
Get matched with trusted local builders
Understand what's allowed on your property
Learn the key rules and size limits for ADUs
Is your property eligible for an ADU?
ADU rules in other Colorado municipalities
Rules change at the town line. Check the municipality your property is actually in.
Pitkin County