Discover how long it takes to build an ADU with our comprehensive guide covering every stage of the construction process. Learn about planning, design, permits, site preparation, foundation, framing, utilities, interior finishing, inspections, and the factors that can impact your ADU timeline. Whether you're building a detached, attached, or garage conversion ADU, Pacific Construction shares expert insights to help homeowners in the San Francisco Bay Area understand what to expect, avoid costly delays, and successfully complete their accessory dwelling unit project on schedule and within budget.