We have Custom Attached ADU plans
We've successfully completed over 100+ projects recently, ensuring 100% client satisfaction, making it our largest portfolio Attached ADU
What Is an Attached ADU?
An attached ADU is a complete, independent home that shares at least one wall with your main house. It has its own entrance, kitchen, bathroom and living space, so it works as a separate residence while staying connected to your existing home. Many Los Angeles homeowners choose this option to add space for family or rental income without giving up the backyard.
Benefits of an Attached ADU
- Keeps your yard open: building off the side or rear of the house leaves more outdoor space than a separate backyard unit.
- Simpler utility connections: water, sewer and electrical lines are close by, which can reduce site work.
- Family close by: ideal for aging parents or adult children who want privacy with support nearby.
- Rental income: a separate entrance and full kitchen make it easy to rent long term.
- Higher property value: a permitted, finished unit adds usable living space to your home.
Attached ADU Rules in Los Angeles
State law sets the main rules for ADUs across California, and Los Angeles follows them with a few local details. Here is what usually applies:
- Size: up to 50% of the main home’s living area, with a 1,200 square foot maximum. At least 800 square feet is protected on most lots.
- Height: up to 25 feet or the height limit of your zone, whichever is lower.
- Setbacks: 4 feet from the side and rear property lines.
- Separate entrance: the unit needs its own exterior door, kitchen and bathroom.
- Parking: often not required, especially within half a mile of public transit.
- Owner occupancy: not required for a standard ADU.
Hillside, fire zone and coastal lots can add extra review, so we confirm these details for your address during the consultation. You can read the state’s rules in the California ADU handbook.
Attached ADU vs Detached ADU
Attached
- Shares a wall with the main home
- Keeps more of your backyard
- Shorter utility runs
- Size tied to the main home
Detached
- Stands on its own in the yard
- More privacy between units
- Up to 1,200 square feet
- Needs open yard space
Not sure which is right for your lot? Compare our detached ADU and garage conversion options, or read the full cost to build an ADU in Los Angeles.
What Affects the Cost?
Cost depends on size, layout, finishes and how the new space ties into your existing home. Structural work, roof connections and fire separation between the units all play a role. During your free consultation, we walk your property and give you a clear estimate for your project before any design work begins.
Attached ADU FAQs
How big can an attached ADU be in Los Angeles?
In most cases it can be up to 50% of the main home’s living area, with a maximum of 1,200 square feet. State law protects room for at least an 800 square foot ADU on most lots.
Do I need to live on the property to build one?
No. California no longer requires owner occupancy for a standard ADU, so you can rent out both the main home and the ADU.
Does the unit need its own entrance?
Yes. It needs a separate exterior entrance, and it must have its own kitchen and bathroom to count as a full ADU.
Do I need to add parking?
Often not. Parking is not required for an ADU within half a mile of public transit, and it is not required to replace a garage converted as part of the project.
How long does construction take?
Design and permits usually take a few months, and construction often takes several more, depending on size, site conditions and plan check times.
Can I rent out the unit?
Yes. Long-term rentals are allowed. Short-term rentals of fewer than 30 days are generally not allowed for ADUs in Los Angeles.
Ready to add more living space? Book a free ADU consultation and we will tell you what your property can hold.
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Licensed ADU construction across Los Angeles, from first sketch to final inspection.
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