
Accessory dwelling unit cost in California
Last updated: September 24, 2026
We build accessory dwelling units (ADUs) across California. Our service reaches major metros like Anaheim, Riverside, Moreno Valley, Oxnard, Elk Grove, and Santa Rosa. California's diverse climate and housing stock shape ADU projects.
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Common questions
What does ADU stand for?
ADU stands for Accessory Dwelling Unit. It's an additional living space on your property. This can be a detached unit or an attached addition. ADUs provide flexibility for housing needs.
Are ADUs allowed in California?
Yes, California has state laws that encourage ADUs. Many cities allow them, though local rules apply. We help you navigate the specific regulations for your property in areas like Anaheim or Riverside. We ensure your ADU meets all requirements.
What is the most expensive part of building an ADU?
The most expensive part of building an ADU is often the foundation and structural framing. These are critical for stability. Connecting utilities like water, sewer, and electricity also represents a significant cost. These are essential for habitability.
How much does it cost to build a 1200 sq ft ADU in California?
The cost to build a 1200 sq ft ADU in California varies significantly. Factors include location, materials, and site complexity. We offer a free phone quote to assess your specific project. We aim to provide clear pricing for your ADU needs.
How much to build a 900 sq ft ADU in Massachusetts?
Building an ADU depends on many variables, including size and design. Local building codes and material costs play a big role. We provide a custom quote based on your unique project. We focus on delivering value for your California home.
What influences ADU costs in California?
Useful reference: HUD ADU resources — ADU policy and financing research.