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  • The Regulations Hub · Updated Monthly

Colorado's two-layer ADU rulebook, explained plainly.

State law sets a floor. Your city sets the rest. Here’s exactly what HB 24-1152 changed, what it didn’t, and what still depends entirely on your address.
  • The state floor

What HB 24-1152 actually requires

Signed into law in 2024, HB 24-1152 requires most Colorado cities with more than 1,000 residents in certain metro areas — including Denver and much of the Front Range — to allow at least one ADU by-right on lots zoned for single-family homes. It also restricts some of the tools cities used to effectively block ADUs, including blanket owner-occupancy requirements and minimum lot-size thresholds set far above what’s needed for a code-compliant unit. The law does not eliminate local zoning. Cities retain control over setbacks, height limits, design standards, size caps (within reason), and permitting procedure. Think of HB 24-1152 as removing the cities’ ability to say “no ADUs, period” — not as replacing every local rule.
  • LAYER 1 · STATE
HB 24-1152 (2024)
Requires by-right allowance of at least one ADU per single-family lot in covered jurisdictions. Restricts owner-occupancy mandates and overly restrictive minimum lot sizes.
  • LAYER 2 · CITY
Denver zoning code
Sets specific setbacks, height limits, size caps relative to the main house, and parking requirements. Denver has gone further than the state minimum by removing owner-occupancy requirements citywide.
  • LAYER 3 · DISTRICT
Historic district design review
52 Denver historic districts layer on additional design review — materials, massing, and visibility from the street can all require sign-off beyond standard zoning.
  • Denver specifics

What's different inside Denver city limits

Signed into law in 2024, HB 24-1152 requires most Colorado cities with more than 1,000 residents in certain metro areas — including Denver and much of the Front Range — to allow at least one ADU by-right on lots zoned for single-family homes. It also restricts some of the tools cities used to effectively block ADUs, including blanket owner-occupancy requirements and minimum lot-size thresholds set far above what’s needed for a code-compliant unit. The law does not eliminate local zoning. Cities retain control over setbacks, height limits, design standards, size caps (within reason), and permitting procedure. Think of HB 24-1152 as removing the cities’ ability to say “no ADUs, period” — not as replacing every local rule.
RequirementDenver rule
Owner-occupancyNot required — a change from Denver's older code
ADUs per lotOne, in most single-family zone districts
Max sizeTypically capped relative to main house size or a flat sq ft limit, by zone district
ParkingOff-street parking requirements vary by zone district and proximity to transit
Historic districtsAdditional design review required in all 52 districts
Permitting pathBuilding permit through Denver's Community Planning & Development; zoning permit may be required first
This table is a starting-point summary, not a substitute for confirming your specific zone district with Denver CPD. Rules shown reflect our most recent fact-check pass.
  • By city

Front Range suburb & city guides

Regulations differ meaningfully by jurisdiction — setbacks, size caps, and owner-occupancy rules aren’t uniform across the metro.
Aurora

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Lakewood
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Boulder
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Fort Collins
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Colorado Springs
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Littleton
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Highlands Ranch
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Wheat Ridge
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Broomfield
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Douglas County
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