KN Remodeling & Supplies INC

What is the cost of an ADU in Los Angeles?

May 9, 2024

Detached ADU

The following cost breakdown is for a 650 sqft detached ADU in Los Angeles.

This small backyard home is what I would describe as custom with many nice upgrades. The building was designed to be ultra-efficient with an air-tight building envelope and insulation well above code requirement.

Upgrades like rift white oak kitchen cabinets and vaulted ceilings in the main living area added to the build cost but gave the finished ADU in Los Angeles a very luxurious feel.

The details that follow are for a new detached custom ADU in or around Los Angeles. It covers everything from initial design and planning, to city permits, to hard construction costs and issuance of the Certificate of Occupancy (CofO).

Cost of Adu in Los Angeles

Keep in mind that all construction projects are unique, and cost will vary depending on the size of ADU you want to build and the quality of construction you desire.

ADU Construction Cost Budget

The following cost breakdown is for a 650 sqft detached ADU in Los Angeles.

This small backyard home is what I would describe as custom with many nice upgrades. The building was designed to be ultra-efficient with an air-tight building envelope and insulation well above code requirement.

Upgrades like rift white oak kitchen cabinets and vaulted ceilings in the main living area added to the build cost but gave the finished a very luxurious feel.

The details that follow are for a new detached custom ADU in or around Los Angeles. It covers everything from initial design and planning, to city permits, to hard construction costs and issuance of the Certificate of Occupancy (CofO).

Line ItemCostComments:
Design & Structural Engineering$12,000The budget included design fees to KN Remodeling Supplies INC for the ADU Design and Structural Engineering. Fees also covered energy modeling per State of Los Angeles Title 24 requirements, and a storm water drainage plan by the Civil Engineer.
Building Permits$8,500All fees required to plan and build the ADU through the City of Los Angeles. Fees included ADU in Los Angeles Department of Building and Safety ($), City of Los Angeles Fire Department to verify there was a fire hydrant close by ($), City of Los Angles Bureau of Engineering ($), and City of Los Angeles Storm water ($).For more detailed information about the cost of an ADU permit in Los Angeles, click here.
Site Prep / Excavation$7,000ADU was built in a backyard that was almost completely flat and required no demolition of any existing structures and very little site prep. This fee covered the trenching on the foundation footings and preparation of the building pad. Also included the hauling of the spoils (i.e. – dirt) that were removed when we trenched the footings.
Site Drainage System & Rain Harvesting$9,000All new construction in Los Angeles requires that any rain that falls on the roof (or other impermeable structures) must be retained on-site and treated. This requires rain barrels to collect all roof run-off and a filtration system to treat the rainwater before it is used for landscaping on sent to the city storm drain.
Concrete Foundation$19,500Our Structural Engineer designed a slab-on-grade foundation for the ADU due to the flatness of the backyard. Our footings were in expansive soil so they needed to be a little deeper than usual, but overall the foundation was relatively inexpensive and easy to build.
Rough Carpentry$26,000Standard 2×6 walls and 2×12 roof joists were used and the amount of structural beams were kept to a minimum to keep the costs of the rough framing relatively low.
Stucco$14,500A smooth “Santa Barbara” stucco siding finish was used on the exterior which gives the home a modern, luxurious feel.
Roofing$12,000A high quality asphalt shingle “cool roof” was installed to match the roof of the existing home. The roof comes with a 30 year warranty and looks fantastic!.
Windows & Exterior Doors$9,500We used Milgard Ultra Series fiberglass casement windows throughout the ADU. The fiberglass windows are a great choice for durability and longevity.
Plumbing$24,600This covered all the rough and finish plumbing and plumbing fixtures for the ADU, but it also included connecting the ADU in Los Angeles to the city sewer and taping into the city fresh water lines.
Electrical$21,500The ADU is set-up with its own electrical meter and panel, so the ADU in Los Angeles can be rented and the renter can pay for their energy usage separately from the main house. Due to the age of the existing electrical panel on the front house the city required that we upgrade the existing panel as part of the project which added money to our budget for electrical.
HVAC$7,200A super-efficient mini split HVAC system was designed and installed for the ADU in Los Angeles.
Insulation$8,500The Title 24 requirement for energy efficiency are already pretty high in the State of Los Angeles , but we decided to increase the efficiency of our ADU even more by adding 2″ of continuous insulation to the exterior of the walls and roof. This additional insulation cost a little more but will improve the comfort in the ADU substantially.
Drywall & Interior Paint$11,500A Level 5 drywall finish was applied to interior walls of the ADU. A Level 5 finish (for those of you unaware) is a full skim coat finish which gives the walls a completely smooth finish. It is the highest level of finish available and gives the ADU in Los Angeles a luxurious wall finish.
Interior Doors$3,800Solid wood interior doors were used throughout the ADU. In such a small home it is important to use solid wood to reduce sound transfer and noise throughout the home.
Millwork (Base & Case)$4,750Nothing too special here. Just traditional solid wood base and case around the floors, doors, and windows. Expertly installed and finished of course!
Kitchen Cabinets$9,500Solid rift white oak kitchen cabinets were used and look awesome! White oak is a very popular choice for high end kitchens and baths and for good reason. It provides a warm natural look and will last a lifetime.
Flooring$6,500Luxury Vinyl Plank (LVP) flooring was used as it is a very beautiful and long lasting flooring option.
Tile & Stone$9,750We opted for a beautiful marble for both the kitchen and bath vanity tops. And the shower and bathroom floor we’re tiled with hand made cement tiles for an earthy finish.
Appliances$6,800A Bosch apartment size appliance package was installed for this ADU in Los Angeles. Great appliances that are well proportioned for the space.
Total$232,400 

So, there you have it. This is just one example of what an ADU costs in (ADU in Los Angeles). I know a lot of you are getting your calculators out to see what the cost per square foot price is for this ADU. After all, that is how we are taught to determine whether we are getting a good deal when building our new home.

Cost of Adu in Los Angeles Per Square Foot

I will save you a few seconds of work; the price was approximately $358 per sqft, which is a little on the high side compared to many ADU in Los Angeles we build. But it is in-line with what you can expect to pay for a well-designed and built home.

I would caution you that calculating the cost-per-square-foot for an ADU can be misleading. You must remember that this is a (small) custom home that is designed and built unique for you and your backyard.

And the ADU comes equipped with a full-size kitchen and full-size bathroom within its modest footprint.

Kitchens and bathrooms are expensive to build on a cost-per-square-foot basis, and for this reason you never get a bid from a builder that states the cost-per-square-foot for kitchens and baths.

Since the ADU is small it simply does not benefit from the same economies of scale that larger homes do. There are no large living room or additional bedrooms that are relatively inexpensive to build as compared to a full-size kitchen.

A better way to look at the cost of a new detached ADU in Los Angeles is to think in terms of the value it is creating. In many neighborhoods ADU in Los Angeles es a new 650 sqft ADU will add $300,000+ to the resale value of the home, which is a phenomenal investment.

But the real benefit is having your aging parent comfortable, or overnight guests relaxing in style and comfort in your backyard instead ADU in Los Angeles of at a hotel down the street. Just imagine how much more enjoyment you will get out of your backyard when there is a small and stylish home there.

If you are considering designing and building an ADU in Los Angeles for any reason, please give us a call or drop us a line to schedule a Free Consultation. We are more than happy to share our knowledge of ADUs and can help you understand what is possible in your backyard.

Good luck and let me know if I can help guide you on your ADU journey.

Who We Are

KN Remodeling is a certified and qualified renovation company that provides renovation services to all people of Los Angeles, Woodland Hills, Simi valley, Thousand oaks, and its environs. As a full time company, we offer a wide range of services and products tailored to make your home beautiful. From replacement of kitchen counter-tops to bathroom flooring, KN Remodeling, does it all. We take pride in what we do and we are always glad to put a smile on your face each time you ask for our services. That is why we have a showroom with certified designers and kitchen remodelers who guide you in deciding what’s best for your bathroom or kitchen. We make our customers feel at home by giving them a wide range of remodeling designs to choose from and we always renovate your home with your needs and wants in mind.