Santa Monica Garage Conversion ADU
A 2-car detached garage transformed into a coastal-style one-bedroom ADU — permitted through Santa Monica's Coastal Zone process and earning $3,200/month in rental income.
All-inclusive project cost covering design, engineering, permitting, construction, and certificate of occupancy.
Challenge, Solution, and Result
Coastal Zone Permitting and HOA Design Review
The property sat within Santa Monica's Coastal Zone, requiring a Coastal Development Permit (CDP) in addition to standard building permits — a process that adds both time and complexity. The homeowner's HOA also had architectural design guidelines requiring new structures to complement the existing Spanish Colonial Revival main residence. The combination of CDP review, HOA approval, and Santa Monica's standard plan check process had the potential to stretch the timeline significantly if not managed carefully.
Parallel Permitting and Coastal-Compliant Design
We initiated the HOA design review and the Coastal Development Permit application simultaneously, rather than sequentially — compressing what could have been a 5-month approval chain into 14 weeks. Our architectural team designed the conversion to echo the main house: stucco exterior, clay tile roof accents, arched window openings, and warm white paint to match the existing palette. The result satisfied HOA review on the first submission. We also identified that the existing garage's stem wall foundation was adequate for habitable use, avoiding a full foundation replacement and saving approximately $18,000 in structural costs.
A Coastal ADU That Earns $3,200/Month
The finished unit is a well-proportioned one-bedroom with 9-foot ceilings, a full kitchen with quartz counters, a walk-in shower, and a private patio enclosed by a new board-formed concrete garden wall. The homeowner secured a 12-month lease at $3,200/month within two weeks of listing — a 21% gross annual return on the construction investment. The ADU also significantly increased the property's appraised value, which the homeowner used to fund a partial refinance.
Build Highlights
The specific decisions, solutions, and features that defined this project.
Phase-by-Phase Breakdown
From initial design through certificate of occupancy — every phase, every duration.
Design & Architecture
4 weeksSite assessment, as-built documentation of existing garage, HOA design package preparation, and full architectural drawing set including interior layout, elevations, and coastal compatibility narrative.
Permitting
14 weeksSimultaneous submission to Santa Monica Building & Safety, HOA architectural review board, and California Coastal Commission. One round of minor corrections from Santa Monica Building; CDP issued without additional review.
Construction
12 weeksFoundation reinforcement, wall framing infill, roof plate raise, mechanical rough-in, drywall, tile, cabinetry, and finish work. One city inspection delay of 5 days mid-project; all other inspections passed first-time.
Final Inspection & Occupancy
1 weekFinal LADBS inspection, utility service activation, and certificate of occupancy issued. Unit listed for rent within 3 days of occupancy permit.
Project Cost: $148,000
All-inclusive — covering architectural design, engineering, permitting, full construction, and certificate of occupancy. No surprises, no change order culture.
- Architectural design and engineering
- All permit fees and city approval management
- Full construction — foundation through finish
- Final inspection and certificate of occupancy
- LocationSanta Monica
- Project Cost$148,000
- Monthly Rent$3,200/mo
- Timeline8 months
Build Something Like This on Your Property
Tell us about your property and goals. We'll confirm what's buildable, recommend the right ADU type and size, and provide a site-specific all-inclusive price estimate — free, no commitment.
- Lot and setback review — confirm your ADU options
- ADU type recommendation based on your goals
- All-inclusive price estimate
- Permit timeline for your city and jurisdiction
Request Your Free Assessment
We respond within 1 business day.
ADU Project FAQs
Answers to what Los Angeles homeowners ask most before starting a project like this one.
How long does the ADU process take from start to finish?
How much does an ADU cost in Los Angeles?
Do I need to live on the property to build or rent an ADU?
Will my property taxes increase when I add an ADU?
Can I convert my garage into an ADU?
Does ADU Build LA handle everything, or will I need to hire other contractors?
Have a question not answered above?
Contact an ADU Specialist200+ ADU Projects Completed in Los Angeles
From the first consultation to the final inspection — every project follows the same disciplined process and is backed by the same team, warranty, and accountability.
Licensed & Insured General Contractor
ADU Build LA holds an active California General Contractor (B) license with CSLB and carries full general liability and workers' compensation insurance. Every subcontractor on your project is licensed, insured, and verified before they set foot on your property.
200+ ADUs Built Across LA County
We've completed over 200 ADU projects — garage conversions, detached new construction, Junior ADUs, and attached units — across every major LA-area city. That depth of experience means we've seen every site condition, every permit challenge, and every construction scenario.
15+ Years of ADU Experience
Since before the 2020 ADU law reforms, we've been building accessory dwelling units in Los Angeles. We've navigated every iteration of state ADU law, local zoning changes, and city permit process updates — institutional knowledge that directly accelerates your project.
Transparent, Fixed-Price Contracts
We don't use time-and-materials billing or open-ended design fees. Every project starts with a detailed all-inclusive fixed price covering design, engineering, permitting, and construction. What we quote is what you pay — no surprise change orders, no scope creep billing.
In-House Permit Management
Our team has submitted hundreds of permit applications across LADBS, Santa Monica, Pasadena, Glendale, Culver City, and other LA-area jurisdictions. We know each city's plan check process, common correction triggers, and expedite options — reducing wait time and managing every step for you.
Single-Contract Design-Build
Under one contract, our in-house team handles every phase — design, engineering, permitting, and construction. You won't need to coordinate between a separate architect and a separate builder. One point of contact, one schedule, full accountability from first sketch to final inspection.
Services Behind This Project
ADU Design & Architecture
Custom ADU designs tailored to your property, lifestyle, and Los Angeles zoning requirements. From concept to permitted plans.
ADU Permitting & Approvals
We handle the full permitting process with the City of Los Angeles and surrounding municipalities — from plan check to final approval.
ADU Construction
Full-service ADU construction from foundation to finish. Licensed, bonded, and experienced in LA County building requirements.
Related City Guide, ADU Model & Projects
Dig deeper into the location, the model used in this build, and other completed projects from our portfolio.
ADU Building in Santa Monica
Serving Santa Monica
Garage Conversion 450
Convert your existing garage into a fully permitted, income-generating ADU — the fastest, most affordable path.
Pasadena Detached Backyard ADU
A new 650 sq ft Craftsman-influenced ADU built in the rear yard of a 1921 bungalow in Pasadena's Bungalow Heaven historic neighborhood. Designed, permitted, and built in under 11 months.
Glendale Junior ADU Remodel
An attached garage and unused bonus room converted into a 480 sq ft Junior ADU on a hillside Glendale lot — navigating structural constraints and earning a multigenerational family its own private living space.
Inspired by this project? Design your own ADU.
Use our interactive configurator to choose type, size, finishes, and style. See matching floor plans and get a budget estimate — before talking to anyone.
Start Your ADU Project Today
Join over 200 Los Angeles homeowners who have added rental income and lasting property value with an ADU from ADU Build LA.