ADU costs in California typically range from $150,000 to $400,000+ depending on size, finishes, and site conditions. A basic 400 sq ft studio might start around $150,000, while a fully-finished 1,200 sq ft two-bedroom unit with high-end finishes can exceed $350,000. We provide detailed, transparent quotes based on your specific project requirements.

The complete ADU process typically takes 8-14 months from start to finish. This includes 2-4 months for design and permitting, and 4-8 months for construction. Timelines can vary based on project complexity, permit processing times in your city, and weather conditions. We'll provide a detailed timeline specific to your project.

Yes, building permits are required for ADU construction in California. You'll need building permits, and depending on your project, you may also need electrical, plumbing, and mechanical permits. The good news is we handle all permit applications and inspections as part of our comprehensive service, making the process stress-free for you.

California has some of the most ADU-friendly laws in the nation. Key provisions include: no owner-occupancy requirement for ADUs, streamlined permitting (cities must approve within 60 days), no parking requirements near transit, reduced setback requirements, and the ability to build both an ADU and Junior ADU on single-family lots. Cities cannot require minimum lot sizes for ADUs under 800 sq ft.

California state law allows detached ADUs up to 1,200 square feet. Attached ADUs can be up to 50% of the existing home's floor area, with a minimum of 800 sq ft allowed regardless of lot size. Some local jurisdictions may have additional requirements. We'll assess your specific property to determine the maximum allowable size for your ADU.

Yes, ADUs typically add significant value to properties. Studies show ADUs can increase property values by 20-30% or more in the Bay Area. Beyond the property value increase, ADUs generate rental income that can help offset mortgage payments or provide retirement income. The combination of increased property value and rental income potential makes ADUs an excellent investment.