ADU Builder Los Angeles - Helping You Build Smarter in LA
Your straightforward guide to building an accessory dwelling unit in Los Angeles, from first questions to final permit.
Areas Covered
This site covers Los Angeles, California. Every piece of guidance here is written with Los Angeles properties, Los Angeles regulations, and Los Angeles costs in mind. References to city departments, setback rules, and fee structures all point to the City of Los Angeles and its governing body, the Los Angeles Department of Building and Safety (LADBS). Neighboring cities and unincorporated county areas follow different codes, so this site stays tightly focused rather than offering advice that may not apply to your address.
Who We Help
This site is for Los Angeles homeowners thinking about adding an accessory dwelling unit (ADU) to their property. That includes first-time builders who have never touched a permit application, as well as owners who have done light renovation work but find the ADU process unfamiliar. The content is written in plain language. You will not need a background in construction or planning to get value from it.
If you are weighing whether an ADU makes financial sense, trying to understand what different project types cost, or figuring out where to start with permits, this site is built for you.
What This Site Is For
ADU Builder Los Angeles exists to close the gap between publicly available regulations and the practical knowledge a homeowner actually needs. City codes and state statutes are technical documents. They answer legal questions, not homeowner questions. This site translates that material into guidance a general reader can act on, covering what the rules mean in practice, what projects typically cost in this market, and how the approval process works at LADBS.
Topic choices are driven by the questions Los Angeles homeowners ask most often. Where regulations or costs shift, the content is reviewed and updated to reflect current conditions rather than left to age.
What This Site Covers
Three core topics run through the site.
ADU permit requirements in Los Angeles covers how the LADBS review process works, what documents a typical application requires, and how long plan check review takes. Standard review runs 4–12 weeks; using LADBS pre-approved standard plans can shorten that window to 1–4 weeks. The site explains setback rules, the 4-foot minimum rear and side setback for detached units, size limits up to 1,200 square feet for a detached ADU, and the 500-square-foot cap for a junior ADU (JADU). It also covers the impact fee waiver available for ADUs under 750 square feet under California state law.
ADU construction costs in Los Angeles gives readers realistic budget benchmarks for each project type. A detached ADU typically runs $150,000–$350,000 all-in, reflecting $300–$500 per square foot for permitted, site-built construction. A garage conversion ADU generally lands between $80,000–$150,000. A JADU conversion, which works within existing habitable space, often costs $40,000–$80,000.
Prefab and modular options installed on site tend to fall in the $200,000–$320,000 range once foundation, utilities, and permits are included. Design and architectural fees commonly add $8,000–$20,000, and city permit fees for Los Angeles projects typically run $10,000–$25,000.
Types of ADUs you can build in Los Angeles walks through the practical differences between detached new construction, garage conversion ADUs, JADUs, and prefab units. Each type carries different cost profiles, timelines, and zoning considerations. Understanding which type suits your lot and budget is often the most useful first step, and this section is written to help you make that call with confidence.