ADU Builder
In Santa Monica
Licensed & InsuredAIA AffiliatedSanta Monica, CA
Detached, attached, and Junior ADUs across Santa Monica and Los Angeles County. Permits managed with the city, honestly priced, built to code.
- Duration
- 2–8 Months
- Scope
- ADU / Extension
- Permits
- Managed In-House
Every ADU Type
Built to Code
An ADU project through Warren Development covers every phase — site assessment, permits, foundation, framing, mechanicals, and interior finishes. Detached, attached, garage conversion, or Junior ADU — one team, one contract.
- 01
Site Assessment
Full lot survey, setback analysis, and feasibility check against Santa Monica's ADU ordinance before design starts.
- 02
Permits & Zoning
Building permit and zoning review handled with the Santa Monica planning department. No third-party expediter.
- 03
Foundation & Utilities
Slab or raised foundation with new electrical, water, sewer, and gas service run to the ADU.
- 04
Framing & Envelope
Structural framing, roofing, siding, windows, and doors. Weather-tight before interior work begins.
- 05
Interior Finishes
Kitchen, bath, flooring, cabinetry, and fixtures specified and installed to match your primary home.
- 06
Handoff & Occupancy
Final walkthrough, punch list, and city inspections. Ready for occupancy or rental on day one.
Four Phases No Surprises
Every ADU project runs the same way — clear estimate, permits secured, coordinated build, walkthrough at handoff.
- 01
Step 01 of 04
Consultation & Feasibility
We walk the lot and check your project against Santa Monica's ADU rules — setbacks, size limits, parking, coastal-zone if applicable. You get a real scope and budget before design starts.
DeliverableFeasibility Report - 02
Step 02 of 04
Design & Permits
We finalize plans, run structural, and file permits with the city. Every fixture and finish confirmed before construction begins.
DeliverableApproved Permits - 03
Step 03 of 04
Construction
Foundation, framing, mechanicals, and interior finishes managed in sequence by our team. One on-site PM from kickoff to handoff.
DeliverableBuilt On Schedule - 04
Step 04 of 04
Walkthrough & Handoff
Final punch list, city inspection, and warranty handoff. Your ADU is ready for occupancy or rental on day one.
DeliverableCertificate of Occupancy
Recent ADU Builds
Across The Westside
View All ProjectsReady to Build
Your ADU?
Send a few project details through the form, or reach us directly Sunday through Saturday, 6am to 7pm. We'll walk the lot with you and put together a clear estimate — no pressure, no obligation.
Or Reach Us Direct
- Open — Sunday to Saturday, 6am to 7pm
- Free on-site quotes — no obligation
- Licensed, insured & bonded — cert on request
- Honest pricing on every project
- 1-year workmanship warranty included
\ FAQ /
ADU
Questions Answered
Five answers to the questions homeowners ask most when planning an ADU across Santa Monica and the Westside.
01
How much does an ADU cost in Santa Monica?
Answer
ADUs in Santa Monica through Warren Development typically range from $200,000 to $600,000+ depending on square footage, whether it's detached or a conversion, and finish tier. Westside labor and material pricing runs higher than national averages — a Junior ADU on an existing footprint sits at the lower end; a detached 1,200 sq ft ADU with custom finishes at the upper end.
02
How long does it take to build an ADU?
Answer
Most ADUs in Santa Monica take 4 to 8 months from permit approval to certificate of occupancy. Add roughly 2 to 4 months for design, structural, and permit review with the city before construction starts. Detached ADUs run longer than garage conversions or Junior ADUs.
03
Do I need a permit to build an ADU in Santa Monica?
Answer
Yes. Every ADU requires a building permit, and detached ADUs additionally trigger zoning review for setbacks, height, and parking. California state law (AB 68 and follow-ons) simplified the review process, but Santa Monica still enforces its own local standards. We handle the entire process with the city planning and building departments.
04
Can I rent out my ADU?
Answer
Yes — California law now permits ADUs to be rented separately from the primary residence, and Santa Monica allows both long-term and short-term rentals subject to STR restrictions. ADUs cannot be sold separately from the main property. We can talk through rental viability during consultation.
05
What's the difference between a detached ADU, attached ADU, and Junior ADU (JADU)?
Answer
A detached ADU is a standalone structure — like a small house on the same lot. An attached ADU shares at least one wall with the main home. A Junior ADU (JADU) is under 500 sq ft, sits inside the primary home's footprint, and can share a bathroom with the main house. Each has different rules for parking, size limits, and setbacks.
ADUs Built
Across The Westside
We build ADUs across nine cities on the Westside and greater LA. Free on-site quotes anywhere in our coverage zone.
- Santa Monica
- Brentwood
- Pacific Palisades
- Westwood
- Beverly Hills
- Venice
- Malibu
- Calabasas
- Marina Del Rey
- Santa Monica
- Brentwood
- Pacific Palisades
- Westwood
- Beverly Hills
- Venice
- Malibu
- Calabasas
- Marina Del Rey