Accessory dwelling unit construction — Boulder, CO
Last updated: September 24, 2026
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
This is the physical process of building your unit, from pouring the foundation and framing the walls to installing plumbing and electrical. Construction quality varies based on your choice of materials and the complexity of the site design. Proper construction ensures your unit is insulated, safe, and meets all energy efficiency standards. You need this service when you have your permits ready and are prepared to build. Exact pricing confirmed free on the call.
Frequently asked in Boulder
What are homes with in-law suites like in Boulder?
Homes with in-law suites in Boulder provide a separate, private living space for family members. These suites offer independence while keeping loved ones close. An ADU is an excellent way to create one. It adds significant value and functionality to your property. We can help design your ideal suite.
Can I find an accessory dwelling unit for rent?
What about accessory dwelling unit financing?
Tell me about prefabricated accessory dwelling units.
Prefabricated accessory dwelling units (ADUs) are built off-site in sections and then assembled on your property in Boulder. This can often speed up construction time. The quality is high, and designs are flexible. We can help determine if a prefabricated ADU is the right choice for you.
What are accessory dwelling unit homes?
Accessory dwelling unit homes in Boulder are properties that include a main house and a separate, independent living unit on the same lot. This second unit is the ADU. It provides additional living space or rental opportunities. It's a smart way to maximize your property's potential. We help you create the perfect ADU home.
What about prefab ADUs?
Prefab ADUs can be a good option for construction in Boulder. They can sometimes offer faster build times and more predictable costs. However, site preparation is still essential. We can help you determine if a prefab ADU is the right choice for your needs and property.
What do accessory dwelling unit builders do?
Also serving nearby: Longmont · Westminster · Arvada · Thornton · Lakewood
More on this: HUD ADU resources — ADU policy and financing research.
Service area details
Serving all of Boulder — population 105,898; about 3,937 residents per square mile across 26.9 sq mi. ZIP codes covered include 80301, 80302, 80303, 80304, 80305, 80306, 80307, 80308.
Neighborhoods served in Boulder: Downtown Boulder, University Hill, Mapleton Hill, Chautauqua, Gunbarrel — and every surrounding area.
Areas we serve
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