ADUs are allowed in ArvadaTypes:DetachedInternal
Types:DetachedInternal
Accessory Dwelling Unit (ADU) Rules for Arvada, CO
Is your property eligible for an ADU?
# of Properties
44,230
Owner-occupied
79%
Zoning districts
40
Avg Home Value
$690,395
Median Lot Size
0.18 acres
Avg Income
$128,008
Residential Types:
44,230 housing units
Single Family
5%
Apts (4+ units)
5%
Other
90%
Zoning Districts:
49,743 parcels · 40 districts
RN-7.5
36%(18,031)
PUD
24%(12,139)
RN-6
13%(6,407)
R24
5%(2,671)
Other
21%(10,495)
ADU Rules
What can you build in Arvada, CO?
Arvada, 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 is the lesser of 40% of the principal dwelling’s living space and a lot-size-based cap (600/850/1,000/1,200 sq ft).
Detached ADU Size Limits
- –Maximum size of 40% of the principal building's living space
- –Maximum size by lot area: 600 sq ft (≤6,000 sq ft), 850 sq ft (>6,000–12,499 sq ft), 1,000 sq ft (12,500 sq ft–1 acre), or 1,200 sq ft (>1 acre), whichever applies
Max Units
- –Single-family detached: 1 ADU/lot (detached or internal).
- –Duplex/townhome/multiplex/multifamily: 0 ADUs
Owner Occupancy
- –Owner must occupy either the principal dwelling or ADU
Parking
- –1 space/ADU; no max; space may be tandem with other required spaces; garage for ADU limited to 250 sq ft; shared/off-site parking ineligible; Zone A reductions may apply but keep 1-space rule.
Rental Restrictions
- –Short-term rentals are prohibited unless licensed; only one dwelling per lot (including an ADU) may be licensed as an STR.
- –If used as an STR, guest occupancy is capped at 240 days per year.
- –Licensees may not operate more than three STR properties citywide at any time.
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.
Adams County