Real Garage Conversion Costs in 2023: Is It Worth It?

Jul 11, 2023 | Garage Conversions, ADU

Cost of Converting a Garage to an ADU in Los Angeles

The cost of converting a garage to an ADU in the Los Angeles area can range from $70,000 for a small garage to $110,000 for a bigger garage (considering those are 2 car garages), depending on your specific circumstances.

This cost estimate includes expenses for plans, contractor labor, materials, and permits required for the garage conversion. Keep in mind that the actual cost may vary based on the size of your garage, existing condition, and the extent of improvements you desire.

The real cost of a garage conversion often surprises most people. Many articles misrepresent the actual expenses involved in converting a garage into an accessory dwelling unit (ADU). While it may be tempting to rely on average cost per square foot figures found online, it’s crucial to ensure that you consider the specific factors affecting the cost. Here are some reasons why garage conversions tend to be more expensive per square foot compared to typical single-family homes:

  1. Fixed Permitting and Design Fees: Regardless of the size of the garage conversion unit, there are certain fees, such as permitting and design costs, that remain constant and must be paid.
  2. Inclusion of Bathroom and Kitchen: Garage conversions require the addition of a bathroom and kitchen, which are considered “expensive” square footage due to the installation and plumbing expenses involved.
  3. Limited Space: Garage conversions are generally smaller in size, lacking the extra bedrooms, spacious living areas, and hallways commonly found in larger homes. These areas, which are considered “cheaper” square footage, would typically lower the average cost per square foot.
  4. New Utility Connections: Unlike room additions, garage conversions are required to have new utility connections, increasing the cost of rough construction.
  5. Fundamental Requirements: Like regular houses, garage conversions need new foundations, plumbing, electrical systems, heating, and cooling provisions, as well as a separate roof.
  6. Size Impact: The cost per square foot can vary significantly depending on the size and structural form of the garage conversion unit. Larger units generally offer a lower cost per square foot. For example, a detached 1,200 square foot unit is likely to be less expensive per square foot compared to a 400 square foot unit.

It’s important to consider these factors when assessing the cost per square foot for a garage conversion, as they can have a significant impact on the overall expenses.

If you’re aiming for an affordable project, here are some tips to help you save costs:

  1. Optimize plumbing layout: Consider positioning the bathroom next to the kitchen to consolidate plumbing needs on a single wall. Similarly, try to position the water heater and laundry area as close as possible to minimize plumbing requirements.
  2. Minimize tile usage: Tile installation can be expensive, so it’s advisable to limit its use. Explore alternative flooring options for all areas, consider alternatives for the kitchen backsplash, and even consider using a fiberglass tub surround in the shower as a cost-saving measure.

By following these tips, you can potentially reduce the overall cost of your garage-to-ADU conversion project in Los Angeles.

2-Car Garage Conversion to ADU Cost Breakdown

Converting a garage is a cost-effective approach to developing an ADU. If you have budget constraints, it’s advisable to retain the existing garage footprint without expanding it.

Two-car garages come in various sizes, ranging from as little as 300 square feet to as large as 475 square feet. Smaller garages are suitable for a studio ADU, while larger ones can be converted into a one-bedroom ADU.

Here are the associated costs:

  1. Design, planning, engineering, and plan check: $6,000.00-$7,000.00
  2. City fees (averaged*): $4,000.00-$5,000.00
  3. Construction labor and materials (averaged* at $200 per square foot): Based on the size range of 2-car garages, the construction cost falls between $60,000.00-$95,000.00.

The total average* cost of converting a 2-car garage into an ADU ranges from $70,000 to $107,000

Although it may seem like a significant investment, let’s consider the return on investment. The average value per square foot for a home in Los Angeles is $714.00 (according to as of May 2023) Comparatively, the average* cost per square foot for developing an ADU from the largest 2-car garage conversion is approximately $225.00.

Can you see the added value? Furthermore, this value doesn’t even factor in the passive rental income generated by the unit. Smaller garage conversions for ADUs in Los Angeles typically rent for an average of $1,750.00 per month.

Note: *Average costs: project costs are dependent on city fees, project location, project size, existing garage condition of framing and foundation, proximity of utility connections and owner selection of finish materials such as; flooring, doors, windows, cabinetry, tile, stone, etc.…

Real Garage Conversion Costs in 2023: Is It Worth It?

Additional Considerations for an ADU Garage Conversion

Sewer Line

To comply with city regulations, it is likely that you will need to install a new sewer line connecting your ADU to the existing sewer lateral in your front yard. Prior to the installation, it is advisable to have your contractor determine the location and depth of the existing lateral to ensure proper connection.

Cost-effective Sewer Line Placement: Running the new sewer line through a dirt area is more cost-effective compared to installing it beneath a concrete driveway. Additionally, running it through the driveway would require tearing up and patching a section of the driveway.

DWP Powerlines

If your property has DWP power lines at the back and your garage is currently situated underneath them, converting it into an ADU may be challenging and bring additional requirements. To explore the possibility of conversion, consider contacting DWP to inquire about relocating the power lines over your garage. Although this option can be expensive and time-consuming, it may be feasible.

Building an Addition

If you intend to expand your garage before converting it into a living space, there are specific considerations to keep in mind. While you can convert your garage into an ADU regardless of its location, any addition you plan to build must adhere to the latest city ADU rules.

  • Setback Requirements: Any addition, whether it’s a single-story or a second-story addition, must be located at least 4 feet away from your side and rear property lines.
  • Size Limitations: Once your garage conversion ADU exceeds 500 square feet, it will need to meet additional city requirements, such as Low Impact Development (LID). Consult your design team for more information on LID guidelines.

City Guidelines

Each city has its own set of city guidelines and requirements for garage conversions and ADUs. It is crucial to reach out to the city building department or hire a local design team who is familiar with the local regulations.


Building a fence between the main home and the garage conversion is a smart way to create privacy. Additionally, consider constructing an access gate specifically for the occupants of the garage conversion.


Particularly for attached garage conversions, it is advisable to include insulation and soundproofing materials between each home to minimize noise transmission between occupants.

Outdoor Area & Patio

Consider providing an outdoor private space for the garage conversion, assuming it is exclusively for the occupant’s use. Creating a concrete patio or installing pavers can offer a suitable surface for seating or dining. Adding a few potted plants or landscaping can enhance the ambiance, but having a lawn might not be necessary. A patio cover for shade is a desirable feature, although it may involve additional costs.

Legalize an ADU

Lastly, if you have an unpermitted garage conversion, now is a good time to legalize it as an ADU. Begin by consulting with a design team to assess the necessary corrections and modifications required to bring it up to code. The process for legalization will be like that of a new garage conversion, involving creating plans, undergoing plan check, performing any required construction work, and finally, obtaining a certificate of occupancy from the city. Legalizing your garage conversion allows you to rent the space and adds value to your property when you decide to sell it.

Convert Your Garage To an ADU Today

Are you considering converting your garage to an accessory dwelling unit (ADU)? Take a look at this comprehensive guidebook on ADU development to gain a general understanding. Additionally, you can schedule a complimentary consultation with Levi Design Build.

Our team is committed to guiding you through every essential phase to transform your garage to an ADU. We are devoted to resolving all your ADU-related queries and assisting you in comprehending the regulations that pertain to your specific location. Together, we can evaluate the advantages and disadvantages of your garage conversion to an ADU. Our highly skilled professionals in design, planning, and construction are prepared to support you in crafting a personalized ADU that fulfills your unique needs.

Contact us today to start converting your garage to an accessory dwelling unit (ADU).