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
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Common Questions
ADU Project FAQs
Answers to what Los Angeles homeowners ask most before starting a project like this one.
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Talk with an ADU specialistOur Track Record
200+ 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.
Services Behind This Project
ADU Plans & Design
Custom ADU plans and architectural design tailored to your property and Los Angeles zoning requirements — from initial concept to permit-ready drawings.
ADU Permits & Approvals
We manage the full ADU permitting process across Los Angeles and LA County — plan check, corrections, and final approval handled end to end.
Detached ADU Construction
New-construction detached ADUs in Los Angeles — from foundation to certificate of occupancy. Full-service design, permitting, and construction under one contract.
Related City Guide, ADU Model & Projects
Dig deeper into the location, the model used in this build, and other completed projects from our portfolio.
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