Cost to build accessory dwelling unit

Looking for cost to build accessory dwelling unit in Denver, CO? Call AccessoryDwellingUnit Direct 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

Thinking about adding an accessory dwelling unit in Denver? It's a smart way to boost your property value and create extra living space in this growing city. The cost can vary quite a bit, depending on the size, materials, and whether you're adding a basement unit or a detached garage conversion. We've seen projects in Denver range from simple backyard studios to more involved multi-story additions. Understand the local zoning laws in Denver – they can significantly impact your project's feasibility and cost. Factors like lot coverage and setback requirements are crucial. It's not just about the build; think about utility hookups and potential permit fees. Don't let the details overwhelm you; getting accurate pricing is the first step. Let us make it easy to get the information you need.

What affects the price

Building an ADU involves variables that shift your total investment. The footprint size and complexity of the architectural design are primary factors. Are you planning a detached unit that requires new utility trenching, or is this a garage conversion that uses existing plumbing? Site accessibility, soil conditions, and your choice of finishes—like luxury flooring versus standard options—also play significant roles. Permitting fees vary widely depending on your local municipality and current zoning requirements. Exact pricing confirmed free on the call.

About this service

The expense of building an ADU varies based on site preparation, whether you need to run new sewer or electrical lines, and the level of interior customization you choose. Larger custom builds naturally require more materials and labor than simpler conversions. We provide exact pricing confirmed free on the call.

Frequently asked in Denver

What are the disadvantages of ADUs in Denver?

Some disadvantages include potential impacts on your existing yard space or privacy. The initial construction cost can be significant, and you'll need to navigate Denver's specific permitting and zoning regulations. However, for many homeowners, the benefits of increased property value and rental income outweigh these concerns.

How much does an ADU cost in Colorado?

What are the rules for ADUs in Colorado?

Colorado's ADU rules are set at the local level, so they vary by city, including Denver. Generally, you'll need to meet minimum lot size requirements, adhere to setback regulations, and ensure sufficient parking. Accessory dwelling units are usually permitted in residential zones, but specific restrictions apply.

Is an ADU allowed in Denver?

Yes, accessory dwelling units are allowed in Denver, but there are specific regulations to follow. These include requirements for lot size, building height, and the number of ADUs permitted per lot. Understanding these rules is key to a successful project in Denver.

What affects ADU costs in Denver?

Several factors influence ADU costs in Denver. These include the size and type of ADU (e.g., detached, attached, basement), the complexity of the foundation and framing, and the finishes you select. Utility hookups and permit fees also contribute to the overall expense.

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, LoDo, Congress Park, Uptown, Highlands, Cheesman Park — and every surrounding area.