Does Colorado distinguish ADUs from detached ADUs?
✓ Verified against code · August 19, 2026
Barely. Colorado's statute treats attached, detached, and interior ADUs as one regulated category, unlike Washington's more detached-specific approach. Cities still draw their own lines: Arvada labels them Type A (detached) and Type B (interior or attached) with different review timelines, and Aurora's outdated code allows only detached ADUs, prohibiting attached and internal ones outright. The abbreviation DADU is essentially absent from Colorado codes — cities simply write 'detached ADU'.
Citation: C.R.S. 29-35-401–405
How current is this?
Colorado’s ADU rules run under HB24-1152 (2024). HB24-1152 (codified at C.R.S. 29-35-401 through 29-35-405) required every Colorado city or town of 1,000+ residents inside a metropolitan planning organization to allow one ADU wherever a single-family home is allowed, through administrative approval, by June 30, 2025 — banning ongoing owner-occupancy mandates (an at-application residency check is allowed), most new-parking requirements, and design standards that would block an ADU in the 500–750 sq ft range. Note the contrast with Washington: one ADU per lot, not two. We verified this answer against primary sources on August 19, 2026, and every change we catch is logged in the changelog.
More Colorado ADU questions
- What is HB24-1152?
- Which Colorado cities are not complying with the ADU law?
- Does Colorado allow two ADUs per lot?
- What happened to Lakewood's zoning code?
- How big can an ADU be in Colorado?
- What is the 500 to 750 square foot size protection in Colorado's ADU law?
- Do Colorado cities require ADU owners to live on the property?
- Can Colorado cities require parking for an ADU?
- What does home rule mean for Colorado's ADU law?
- What do Colorado ADU permits cost?
- How long does it take to get an ADU permit approved in Colorado?
- Can I rent out my Colorado ADU short-term on Airbnb?
- Is a casita the same thing as an ADU?
Not legal advice — local ordinances can go further than the state floor. The citation above points at the governing statute; check your city’s code for the specifics.