Cost of accessory dwelling unit — Denver, CO

Looking for cost of accessory dwelling unit in Denver, CO? Call AccessoryDwellingUnit Pros for a contact a provider — no obligation. Licensed adu builders serve Denver and the surrounding area, and you'll get straight answers on timing and what affects the price.

Last updated: September 24, 2026

What affects the price

Building an ADU is a custom project, so costs vary based on your specific choices. Site conditions are the biggest factor; if your land requires significant grading, utility extensions, or foundation work, those expenses add up quickly. Choosing high-end finishes, custom cabinetry, or complex roof lines will also push the budget higher compared to a standard design. Prefabricated units often offer predictable costs, while custom site-built structures allow for more flexibility but can be harder to estimate upfront. Exact pricing confirmed free on the call.

About this service

The total investment for an ADU depends on several moving parts, including your property’s site conditions, the complexity of your site plan, and the high-end finishes you select. Whether you are building a detached cottage or converting a garage, costs vary based on utility connections and local labor rates. Exact pricing confirmed free on the call.

Frequently asked in Denver

What are the disadvantages of ADUs?

Disadvantages can include upfront construction costs and potential zoning restrictions specific to your Denver neighborhood. You'll also need to consider ongoing maintenance for the new unit. It's important to weigh these against the benefits of added space or income.

How much does an ADU cost in Colorado?

What are the rules for ADUs in Colorado?

Colorado has state-level ADU laws, but Denver also has its own specific zoning ordinances. These dictate things like lot coverage, setbacks, and parking requirements. Pros can explain how these apply to your Denver property.

Is ADU allowed in Colorado?

Yes, ADUs are generally allowed in Colorado, with local municipalities like Denver having their own regulations. Many cities encourage ADUs to address housing needs. We can help you understand the specific rules for your Denver location.

What are the rules for ADU in Colorado?

Colorado ADU rules are supplemented by local Denver ordinances. These cover everything from the maximum size of the unit to how it integrates with your existing home. Understanding these details upfront is key to a smooth build.

Also serving nearby: Aurora · Thornton · Centennial · Westminster · Lakewood

All cities in Colorado →

More on this: HUD ADU resources — ADU policy and financing research.

Service area details

716,577residents

4,681per sq mile

8ZIP codes served

Serving all of Denver — population 716,577; about 4,681 residents per square mile across 153.1 sq mi. ZIP codes covered include 80201, 80202, 80203, 80204, 80205, 80206, 80207, 80208.

Neighborhoods served in Denver: Capitol Hill, Cherry Creek, Highlands, LoDo, Uptown — and every surrounding area.