A two-car garage addition is both a practical storage/parking solution and, increasingly, an investment in future ADU potential. Many LA homeowners are building garages now with an eye toward future conversion to a permitted ADU unit when needed.
Why Add a Detached Garage in LA
Parking. Many Valley homes have a single-car garage or no garage — particularly older homes in Van Nuys, North Hollywood, Sun Valley, and similar neighborhoods. A two-car garage adds parking for a household with multiple vehicles.
Storage. A 20x20 two-car garage adds 400 sq ft of dedicated storage space — significant in Valley homes where interior storage is often limited.
Future ADU potential. California's ADU legislation makes a detached garage one of the easiest paths to a legal ADU. Building a garage today with higher ceiling heights (10'–12'), electrical service, and good structural construction positions the property for future ADU conversion without significant structural rework.
Value. A permitted, attached or detached garage adds meaningful appraised value — typically $60,000–$120,000 to a Valley property depending on location and quality.
What a Two-Car Garage Addition Costs
| Scope | Cost Range | |-------|-----------| | Basic 20x20 detached garage (standard) | $55,000–$90,000 | | Mid-range 20x22 with insulation, drywall, electrical | $75,000–$120,000 | | ADU-convertible garage (10' ceilings, upgraded electrical, plumbed for future) | $90,000–$160,000 | | Finished garage (epoxy floor, storage systems, full electrical) | $100,000–$200,000+ |
Key Design Decisions
Ceiling height. Standard residential garages: 8-foot plate height. ADU-convertible: 10–12 foot plate height minimum (provides adequate clearance for habitable ceiling once floor is raised over slab and finish ceiling is added). If you're planning future conversion, build at 10'+ plate height from the start.
Structural system. Wood frame stud construction is standard. Consider engineered lumber (LVL beams) at the garage door opening for wider openings and less post obstruction.
Electrical. Minimum: lighting, a 20-amp circuit for outlets, a dedicated 240V circuit for EV charging. ADU-convertible: full subpanel (100 amp minimum), wiring for future kitchen and bathroom circuits.
Plumbing rough-in. If there's any chance of ADU conversion, rough in a drain line under the slab during construction. Cutting a slab for later drain installation is expensive and disruptive.
Permit Process
Detached garage additions require building permits. LADBS for City of LA properties; the applicable city building department for Valley municipalities. Requirements:
- Site plan showing setbacks (typically 5-foot side and rear setbacks for accessory structures)
- Structural plans
- Title 24 energy compliance (California's energy code applies to garages with conditioned space)
- Grading plan (if site involves significant slope)
For two-car garage additions and ADU-convertible garage construction in Los Angeles, contact us.
Related: Garage Conversion in Los Angeles · ADU Construction in Los Angeles