ADU Construction in Los Angeles in West Los Angeles
Serving 90025 · 90064 · 90066 · 90034 and Sawtelle, Mar Vista, Palms
California's ADU laws have made backyard units one of the highest-leverage property improvements an LA homeowner can make. We design and build all three types — detached new builds, attached additions, and JADUs (Junior ADUs converted from existing space). End to end. Permits, plans, foundations, framing, finishes, and final inspections, all under one roof. You work directly with Onn from feasibility study through certificate of occupancy.
ADU Construction in Los Angeles specifically for West Los Angeles
Every neighborhood has its own architectural character, permit jurisdiction, and finish-level expectations. Here's how we approach adu construction in los angeles in West Los Angeles specifically.
Post-war housing stock
A lot of West LA homes were built between 1945–1970 and still have original electrical service, single-pane windows, and galvanized plumbing. We plan to address those during a kitchen or bath remodel since the walls are open.
LA City permit reality
West LA falls under LADBS (LA Department of Building and Safety). Plan check timelines run 4–10 weeks for structural work, faster for cosmetic remodels. We pull permits in-house.
Lot-line constraints
Many West LA lots are 50'×130' or similar — tight for ADU additions. We design around setbacks rather than fight them, and propose attached or JADU options when detached doesn't pencil.
What we handle
Feasibility & site planning
Lot review, setbacks, height limits, utility access, soil assessment. We tell you up front whether your project pencils — square footage, code constraints, expected timeline.
Architectural design
Floor plans, elevations, 3D renderings. We design to maximize functional space within California's ADU size limits (up to 1,200 sq ft detached, 850 sq ft for studios/1-bedroom).
Permits & utilities
Plan check submission, energy compliance (Title 24), structural engineering, separate or shared utility service. We deal with LADBS or your municipal building department.
Foundation, framing, finish
New foundations or attached construction, framing, MEP rough-in, exterior, and full interior finishes — kitchen, bath, flooring, HVAC, electrical.
Final inspection & C of O
Final inspections, Certificate of Occupancy, and walkthrough. We hand you a unit you can live in, rent, or use as a guest house.
Pricing in West Los Angeles
Typical detached ADU build cost in Los Angeles, all-in (design, permits, construction, finishes, utility hookups). Attached ADUs typically run lower; JADUs converting existing space lower still.
LA Department of Building and Safety (LADBS) handles permits. Online submission for cosmetic work; in-person plan check for structural. Average plan check: 4–10 weeks depending on scope.
Frequently asked
How big can my ADU be in Los Angeles? +
California state law allows detached ADUs up to 1,200 sq ft (or larger if your local jurisdiction permits). Attached ADUs are limited to 50% of the primary home's square footage or 1,200 sq ft, whichever is less. Junior ADUs (JADUs) are capped at 500 sq ft and must be inside the existing primary structure.
How long does an ADU project take? +
Plan to design and build a detached ADU in 9–14 months total: 2–3 months for design and permits, 6–10 months for construction. Attached ADUs and JADU conversions can run shorter.
Do you do projects under $100k? +
Yes. Single-bath remodels, kitchen refreshes, garage conversions — all routinely under $100k.
Can you handle older home surprises (knob-and-tube, galvanized pipes)? +
Yes — we test and plan for them up front rather than discover them mid-project. Older-home contingency is a built-in budget line on West LA jobs.
From the blog
ADU vs Garage Conversion: Which Makes Sense for Your LA Property?
A clear-eyed comparison of detached ADUs, attached ADUs, JADUs, and garage conversions for LA homeowners — costs, timelines, ROI, and which one fits your lot.
LA County Kitchen Permits Explained (2026 Edition)
When you actually need a permit for a kitchen remodel in Los Angeles, how the plan-check process works, typical timelines for LADBS and surrounding cities, and how to avoid the common mistakes.
ADU Construction in Los Angeles in other neighborhoods
Live in West Los Angeles?
Onn personally reviews every inquiry. Tell us about your project — Onn will be in touch within one business day.