Accessory dwelling unit — 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
An ADU is a versatile housing option that adds extra living space to your property. Whether you need a place for an aging parent, a rental unit, or a quiet workspace, an ADU provides a permanent solution. Because they are secondary to your main house, they are smaller and designed to fit within existing property lines. They are a popular way to expand your home without moving. Exact pricing confirmed free on the call.
Frequently asked in Boulder
What are the first steps for adding a home with an in-law suite in Boulder?
Who is an accessory dwelling unit contractor in Boulder?
What is a 24-hour ADU service in Boulder?
What are modular accessory dwelling units in Boulder?
Modular accessory dwelling units in Boulder, Colorado, are built in sections off-site. These sections are then transported and assembled on your property. This method can sometimes speed up construction. It also ensures a controlled building environment. A professional can advise if this is suitable for you.
What is the ADU cost in Boulder?
What is an ADU permit in Boulder?
What is the accessory dwelling unit cost in Boulder?
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: University Hill, Newlands, Mapleton Hill, Downtown Boulder, Whittier — and every surrounding area.
Areas we serve
Browse by state, then city.