Why Highlands Ranch Is One of the Best ADU Markets in Colorado
Highlands Ranch is one of the largest planned communities in the country, home to over 105,000 residents across nearly 24,000 households in unincorporated Douglas County. With an average home value approaching $580,000, generous lot sizes, and a community that is aging into multigenerational housing needs, it represents one of the strongest ADU opportunities in the Denver metro area.
Until recently, the community's extensive HOA governance made ADU construction effectively impossible for most homeowners. Colorado's HB 24-1152 changed that entirely.
HOA Rules and ADUs in Highlands Ranch
Highlands Ranch is governed by the Highlands Ranch Community Association (HRCA) along with numerous sub-associations that manage individual neighborhoods. Before HB 24-1152, these associations had broad authority to prohibit accessory structures, including ADUs.
Under Colorado's HB 24-1152, effective June 30, 2025, HOAs in subject jurisdictions — which includes all of Highlands Ranch — cannot ban ADU construction. Your association can still enforce what the law defines as "reasonable restrictions." In practice, this means they can require your ADU to match the primary home's exterior — siding material, roof pitch, color scheme — but they cannot deny your project outright.
What Highlands Ranch HOAs can and cannot do under HB 24-1152: They CAN require matching siding, roof pitch, and exterior colors. They CAN require architectural review for design compliance. They CANNOT ban ADU construction. They CANNOT impose requirements more restrictive than those applied to other accessory structures. They CANNOT require a public hearing or neighbor approval.
We understand how Highlands Ranch sub-associations and architectural review processes affect ADU planning. During your consultation, we review your specific HOA's CC&Rs and design guidelines so you know what a qualified designer or builder will need to address from the start.
ADU Types That Work Best in Highlands Ranch
Detached Backyard Cottages
Many Highlands Ranch lots offer generous rear yards that accommodate a detached ADU. The rolling terrain throughout the community also creates opportunities for walk-out or daylight configurations that maximize natural light and create a ground-level entrance. Detached ADUs in Highlands Ranch typically run $200,000 to $400,000 depending on size and finishes, and produce the highest rental income and property value increase of any ADU type.
Basement ADU Conversions
The terrain in Highlands Ranch means many homes have walk-out or garden-level basements — an ideal foundation for a basement ADU. Adding a separate entrance, kitchenette, bathroom, and proper egress creates a fully independent living unit at a fraction of the cost of new construction. Basement conversions in the area typically cost $40,000 to $120,000 and can be completed in 2 to 5 months.
Garage Conversions
Homes with detached or oversized attached garages can convert unused garage space into a living unit. This works especially well for three-car garages where one or two bays can be converted while maintaining parking. Garage conversions typically cost $50,000 to $150,000 and offer a strong balance of affordability and functionality.
Highlands Ranch ADU Zoning and Permits
Highlands Ranch falls within unincorporated Douglas County, which means ADU permits are processed through Douglas County Community Development rather than a municipal planning office. The county has updated its regulations to comply with HB 24-1152, and ADU applications now follow an administrative approval process — no public hearings are required if your plans meet objective standards.
Key zoning considerations for Highlands Ranch ADU projects include setback requirements (which cannot be more restrictive than those for the primary dwelling), lot coverage limits, building height restrictions, and utility connection requirements. Denver Water serves parts of Highlands Ranch and requires a separate water supply license for ADUs, along with a system development charge.
We help you understand the permitting path before you hire a ADU professional — from likely application requirements to plan review, revisions, and final approval. When you are ready to move forward, we can refer you to independent ADU professionals familiar with Douglas County's requirements.
Rental Income Potential in Highlands Ranch
The south Denver metro rental market supports strong ADU rental income. One-bedroom units in the Highlands Ranch area command $1,500 to $1,800 per month, while two-bedroom ADUs can fetch $1,800 to $2,300 or more. A well-designed ADU generating $2,000 per month produces $24,000 annually in rental income.
Beyond rental income, ADUs provide significant lifestyle value for Highlands Ranch families: housing aging parents close by while maintaining privacy, providing space for adult children returning home, or creating a dedicated home office entirely separate from the main residence.
Explore Your Highlands Ranch ADU Options
Whether you are exploring a backyard cottage, considering a basement conversion, or wondering if your garage could become a living space, we start with a free advisory consultation. We review your lot, verify zoning eligibility, check your HOA's specific requirements, outline likely costs, and explain which builder path may fit your goals — all at no cost and no obligation.
Ready to explore your ADU options in Highlands Ranch? start with the ADU quiz. We will evaluate your property's ADU potential and help you understand next steps before choosing a builder.