Garage Conversion Contractor for Los Angeles and the San Fernando Valley
Turn the garage you already have into a permitted living unit — assessed honestly, permitted in the right jurisdiction, and built under one licensed contract.
Hillstar Construction Inc is a licensed and WC insured general contractor (CSLB #972213) serving Los Angeles since 2010, led by founder Lior Mazor, who brings over 40 years of hands-on construction experience. A garage conversion is one of the most cost-effective paths to an accessory dwelling unit because the foundation, slab and parts of the envelope are already there — but a garage built for cars is not built for living, and the right contractor names what has to change before quoting. That is how we work, from Woodland Hills and West Hills across the Valley to Glendale, La Crescenta and the Westside.
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24-Hour Response · Licensed & WC Insured (CSLB #972213)
ADU & Garage Conversions
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Hillstar Construction Inc · CSLB #972213 · Free estimate, no obligation. Call 310-975-7590.
What a Garage Conversion Really Involves
Most older Los Angeles garages were built to vehicle code, not to habitable code. Converting one into an ADU or living space means bringing the existing structure up to current requirements, and a quote that does not name each of these has not actually scoped the job:
- Structural assessment. Existing framing, headers and footings often need upgrading to meet residential structural code, and the slab is checked for level, cracks and moisture staining.
- Moisture barrier and insulation. Slab moisture barriers were rarely installed in older garages, and walls and ceilings are insulated to current Title 24 energy compliance.
- Electrical, plumbing and HVAC. A garage typically has limited electrical, no plumbing and no heating or cooling. Habitable space means new circuits and panel or sub-panel sizing, plumbing rough-in, and an HVAC plan — work we subcontract to appropriately licensed specialty contractors we oversee.
- Egress, light and ventilation. Bedroom egress windows, ventilation and natural light to habitable-room standards.
- Fire separation. Where the garage shares a wall with the house or has occupied space above it, fire-rated assemblies apply between the new living space and the home.
Our guide to choosing a garage conversion contractor in Los Angeles walks through how to read a conversion quote line by line.
Permits, by Jurisdiction
A garage conversion is permitted work everywhere we build: a building permit plus electrical, plumbing and mechanical permits, with inspections through final. Who issues them depends on where the house sits, and we confirm that before anything is drawn.
City of Los Angeles. Most of the San Fernando Valley — Woodland Hills, West Hills, Canoga Park, Encino, Tarzana, Sherman Oaks, Studio City, Northridge, Reseda and North Hollywood among them — is in the City, so the permit is an LADBS permit. LADBS describes an ADU as a small, separate living space on the same property as a single-family home that can be attached to the main house or a separate structure such as a converted garage or backyard cottage. Our team typically files Valley plans at LADBS’s Van Nuys office, as a matter of our own practice.
Other cities and the County. Glendale, Pasadena, Calabasas, Beverly Hills, West Hollywood and unincorporated Los Angeles County each have their own building department instead of LADBS, and we manage that jurisdiction’s process the same way. In unincorporated areas such as most of La Crescenta, the ADU goes to LA County Regional Planning for review and then to LA County Public Works Building & Safety for the building permit, both through the County’s EPIC-LA system.
What state law settles everywhere. For an existing garage or accessory structure converted in place, state ADU law requires no setback, and it does not allow the local agency to require the off-street parking you lose to be replaced. An ADU application is considered ministerially, without discretionary review or a hearing, and must be approved or denied within 60 days of a complete application when there is an existing home on the lot. The details for your address are in our Los Angeles remodeling permit guide.
Attached Garage, Detached Garage, or a Different Path
Detached garages are the simpler conversion: no shared wall with the house, so no fire-separation question, and the electrical and plumbing routing is a matter of distance to the panel and the sewer line. Attached garages need fire-rated assemblies between the new habitable space and the primary home, plus electrical, plumbing and HVAC routing through or around the connection.
Sometimes the garage is not the right answer. When the shell is failing, or the yard is deep, a detached new-build ADU can be the better project; when the garage is attached and the household needs a small separate suite, a junior ADU carved out of the existing house may fit. LADBS states that detached ADUs built from scratch must have solar panels; a conversion inside the existing footprint is a different permit category, and we confirm which energy requirements apply to your project during design rather than assuming.
We compare the options at the site visit. Two of our guides go deeper: garage conversion versus a JADU, and heating and cooling the finished unit with a mini-split system for an ADU or garage conversion. For the full picture of detached, attached and junior units, see our ADU construction hub.
What Drives the Cost, and How We Quote It
A conversion is often less than a detached ADU because the footprint already exists, but older garages can need enough structural, moisture and mechanical work to close that gap. The honest number comes after a site visit, and it comes in writing with each line separated: slab and structural work, framing upgrades, electrical, plumbing and HVAC, insulation and drywall, windows and doors, finishes, and the soft costs of design, structural engineering, Title 24 documentation and permit fees.
The issues we see most often in older Los Angeles garages: a slab not poured for habitation that needs a moisture-barrier retrofit or leveling; an original electrical service too small to carry the new unit plus the house; a sewer lateral far enough away that the plumbing run crosses the yard or the driveway; a garage that sits closer to the property line than current rules would allow for new construction, which affects what kind of conversion is permitted; and no fire-rated assembly between an attached garage and the house. A contractor familiar with LA garage stock names these without prompting.
Scope changes are documented and priced in writing before they proceed. No surprise allowances.
How the Build Runs
Every conversion starts with a site visit: we look at the slab, framing, roof, panel location and sewer line, confirm whether the garage is attached or detached, and confirm the jurisdiction. Then design, structural engineering and Title 24 documentation, and the permit submittal to LADBS or the applicable city or County office.
Hillstar Construction Inc holds the prime contract and manages the entire build: our crew handles foundation and slab work, framing, drywall and finish work directly, and we subcontract electrical, plumbing and HVAC to appropriately licensed specialty contractors we oversee on your behalf. The sequence is demolition and prep, structural and slab work, rough framing, mechanical rough-ins and inspections, insulation and drywall, finishes, and the final inspection with the jurisdiction’s building department. Every finished unit includes a full kitchen and a bathroom, finished to the level you choose with the same care as our bathroom remodeling work, and the project closes with a walkthrough, a punch list and our written workmanship warranty.
Frequently Asked Questions
Do I need a permit to convert a garage in Los Angeles?
Yes. Any habitable conversion needs a building permit plus electrical, plumbing and mechanical permits, from LADBS in the City of Los Angeles or from the applicable city or County building department elsewhere. Doing the work without a permit creates problems when you sell or refinance later, plus code-enforcement exposure.
Do I lose my parking when I convert the garage?
Typically the conversion removes the parking, and state ADU law does not allow the local agency to require that those off-street parking spaces be replaced. Some neighborhoods carry conditions of their own, and we confirm them for your address before design.
Is a garage conversion always cheaper than a detached ADU?
Often, but not always. The footprint is already there, which saves on foundation and parts of the envelope. Older garages can need substantial structural, mechanical and moisture remediation that closes the gap. The honest answer comes after a site visit, in an itemized written quote.
What if my garage is attached to the house?
Attached garages need fire-rated assemblies between the new habitable space and the primary home, plus electrical, plumbing and HVAC routing through or around the connection. Detached garages skip the shared-wall question. Both are common conversions, and both are permitted work.
Does Hillstar handle the permit submission and the specialty trades?
Yes. Design, structural engineering, Title 24 documentation and the permit submission are inside the scope, with LADBS or the applicable city or County office. Hillstar Construction Inc holds the prime contract; electrical, plumbing and HVAC are performed by appropriately licensed specialty contractors we oversee.
Where does Hillstar build garage conversions?
Across Los Angeles, with a focus on the San Fernando Valley and the Westside. Our office is in Woodland Hills, next door to West Hills and Canoga Park, and we work from Northridge and Porter Ranch across to Sherman Oaks and Studio City, out to Glendale, La Crescenta, Pasadena and Beverly Hills.
Hillstar was great! We did a garage conversion and Lior was the best. He helped us plan every detail.
— Jeffrey Rhodes, January 2019Lior was such a pleasure to work with for our guest house remodel. He was so easy to get in touch with, incredibly responsive and finished the job early.
— Amy Christine, February 2019Hillstar Conversion and ADU Work
Real Hillstar Construction Inc jobsites and finished projects in the Los Angeles area. The design and finish level for your garage are set with you at the consultation.
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Garage Conversions and ADUs in Your Neighborhood
We convert garages and build ADUs across the greater LA area. Tap your neighborhood for the local permit path, lot patterns and rules specific to your city:
Full-Service Construction Across Los Angeles
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