ADU guide · Los Angeles
ADU contractor in Los Angeles.
What an ADU actually is in LA
An Accessory Dwelling Unit (ADU) is a second, self-contained home on a single-family or multi-family lot. In Los Angeles, three forms cover almost every project we build: a garage conversion that turns an existing structure into a legal unit, a detached ADU built new in the back yard, and a Junior ADU (JADU) carved out of the main house under 500 sq ft.
California state ADU law preempts most local restrictions — including setbacks, parking and FAR — which is why so many LA homeowners now qualify even when older zoning seemed to block them.
Garage conversion vs detached ADU
Garage conversion
$150K – $250K
Reuses the existing slab and walls. Fastest path to a rentable unit — usually 3–4 months. Setbacks don't apply, so almost any LA garage qualifies.
Detached new-build
$300K – $550K
Up to 1,200 sq ft, two stories where lot allows. More design freedom and resale impact, but adds 3–4 months for foundation, framing and full MEP rough-in.
For most LA properties we walk, the right choice comes down to whether the existing garage is structurally sound and whether the owner wants to keep covered parking.
The ADU process, step by step
01
Feasibility walk
We measure the lot, check existing structures, pull zoning and confirm what you can build before any money is spent on design.
02
Design & plan set
Architectural, structural, Title 24 energy and MEP — a complete plan set ready for LADBS plan check. Usually 4–6 weeks.
03
Permit & plan check
Submitted to the LA Department of Building & Safety. Most ADU plans clear in 6–10 weeks via the standardized ADU review.
04
Construction
Foundation, framing, rough MEP, insulation, drywall, finishes. We run one crew per project, no rotating subs.
05
Inspections & final
LADBS signs off rough framing, MEP, insulation and final. Certificate of Occupancy lands in your hands.
Permits and LADBS — what to expect
Every habitable ADU in Los Angeles needs a building permit from LADBS, plus separate electrical, plumbing and mechanical permits that we pull on your behalf. State law caps plan-check turnaround at 60 days for compliant ADU submittals, and LA's standardized ADU program has cut typical wait times further.
We handle the entire submittal, respond to plan-check corrections, and coordinate every inspection. You sign two documents — the contract and the owner-authorization form — and we take it from there.
Common questions
How long does an ADU take to build in LA?
Garage conversions: 3–4 months on site. Detached new-builds: 6–9 months. Add 2–3 months on the front end for design and permitting.
What does an ADU cost?
Garage conversions in LA generally run $150K–$250K turnkey. Detached ADUs run $300K–$550K depending on size, finish level and site conditions like grade or utility distance.
Do I need to add parking?
No. State ADU law removes the parking requirement for ADUs within half a mile of transit, which covers most of the LA basin.
Can I rent it out?
Yes. ADUs can be rented long-term immediately. Short-term rental (under 30 days) is restricted under LA's Home-Sharing Ordinance.
Will it raise my property taxes?
Only the added value of the ADU is reassessed — the rest of your property keeps its existing assessed value under Prop 13.
Ready to start?
Talk to an ADU contractor who's built across every LA neighborhood.
We'll walk your property, give you a realistic budget and timeline, and tell you straight whether a garage conversion or detached build makes more sense for your lot.