Quick answer: Building an ADU costs $40,000–$380,000 in Los Angeles, depending on the type — garage conversion, attached, or detached new construction. APLA Construction (CA Lic #1136359) provides free estimates across Greater Los Angeles.
California’s ADU laws have made Los Angeles one of the most ADU-friendly cities in the nation. As a licensed ADU contractor in Los Angeles, APLA Construction Group helps homeowners add rental income, house family members, or increase property value through expertly built Accessory Dwelling Units across all of Greater LA.
| ADU Type | Typical Cost |
| Garage conversion ADU | $80,000–$150,000 |
| Detached ADU (400–600 sq ft) | $130,000–$220,000 |
| Detached ADU (600–1,200 sq ft) | $200,000–$380,000 |
| Junior ADU (JADU) | $40,000–$80,000 |
All costs depend on site conditions, finish selections, and permit complexity. Contact APLA for an accurate, itemized quote.
Three questions shape an ADU project before a single drawing is finalized. How big it can legally be — in the City of Los Angeles a detached ADU can be up to 1,200 square feet and a JADU 500, and state law guarantees room for at least an 800-square-foot ADU, though lot coverage and setbacks often bind first, which our guide to ADU size limits in Los Angeles works through. How it gets built — we set factory and site construction side by side in prefab ADU vs stick-built ADU, including why prefab rarely ends up cheaper once site costs land. And what it does to your tax position — see ADU tax benefits in California for how Proposition 13 reassessment, rental income and impact-fee exemptions actually work.
Most single-family and multi-family lots in Los Angeles are now eligible for at least one ADU under California state law (SB 9, AB 68, AB 976). APLA evaluates your specific lot, zoning, and setback requirements during the free consultation at no cost.
From initial consultation to certificate of occupancy, expect 8-14 months for a detached ADU. Garage conversions can be faster – typically 4-8 months depending on permit turnaround at LADBS and site complexity.
As of 2026, California law (AB 976) does not require owner occupancy for ADUs on single-family lots. You can rent both your main home and your ADU simultaneously.
Under California law, building an ADU triggers a partial reassessment only of the new ADU construction – not your entire home. Your existing home’s assessed value remains unchanged.
Yes. Common financing options include cash-out refinancing, home equity lines of credit (HELOC), construction loans, and ADU-specific lending programs. Contact APLA and we can connect you with trusted local lenders.
APLA Construction serves all of Greater Los Angeles – from the San Fernando Valley and West LA to Long Beach, South Bay, Malibu, and Pasadena. detached, attached and garage-conversion ADU builds
Phone: (818) 818-4419
Email: info@aplaconstruction.com
License: CA #1136359 — verify on CSLB
APLA Construction provides ADU Contractor services throughout Greater Los Angeles. Click your neighborhood to see local pricing and details.