How long does it take to build and addition or ADU?
Most of our ADUs take between 4 and 12 months from start to finish, depending on the type of ADU, permitting timelines, and project complexity. Having an experienced contractor who submits complete plans the first time makes a significant difference in how fast things move.
How much does an ADU cost to build in Los Angeles?
Winter Remodeling Inc. builds ADUs between $325 and $450 per square foot depending on your finishes and scope. That includes plans, permitting coordination, and full project management from day one to final inspection.
Do I need a permit to build an ADU?
All ADUs require permits through your local building department. The good news is that Los Angeles County now requires permit decisions within 60 days, and online submissions have made the process faster and more predictable.
Can I rent out my ADU?
Absolutely. California permanently removed owner occupancy requirements for ADUs, meaning you can rent your ADU without living on the property. Rental income typically ranges from $1,500 to $3,500 per month depending on size and location.
What is the difference between an ADU and a JADU?
An ADU is a fully self-contained unit with its own kitchen, bathroom, and entrance and can be detached or attached to the main home up to 1,200 square feet. A JADU is a smaller unit carved out within your existing home, capped at 500 square feet, and requires the owner to live on the property..
Will an ADU increase my property taxes?
Only slightly. Your existing home’s assessed value stays the same under Proposition 13. The tax increase applies only to the value of the newly constructed ADU. SB 1164 also provides a property tax exemption for up to 15 years on new ADUs.
How many ADUs can I build on my property?
Single family lots can add one ADU plus one JADU. As of 2025, multifamily properties can add up to eight detached ADUs thanks to SB 1211, as long as the number does not exceed the existing units on the property.
Can I build an ADU in a historic district or on a historic property?
Yes, you can build an ADU in a historic district or on a property subject to historic preservation, such as under the Mills Act. While local agencies may impose standards to protect historic resources, these standards must be objective and cannot overly burden the creation of ADUs.
What are the setback requirements for a detached ADU?
Detached ADUs in Los Angeles County typically require a 4 to 5 foot setback from side and rear property lines. Setbacks can vary based on your specific zoning district, so having your lot reviewed early in the process is always recommended.
What Are ADU Setback Requirements – City of Los Angeles
1. Standard Setbacks (LA Municipal Code § 12.22.A.33)
• Side & Rear Yards: 4 feet minimum
• Front Yard: Must comply with zoning setback requirements for the main dwelling.
2. Garage Conversions
• No additional setbacks required if using the existing footprint (CA Gov. Code §
65852.2(e)(1)(A)).
3. Multifamily Properties (LA Municipal Code § 12.22.A.33(c))
• Detached ADUs: 4-foot side and rear setbacks apply.
• Converted ADUs (inside existing structures): No setback required.
Can my HOA stop me from building an ADU?
No. Under California state law, HOAs cannot prohibit ADU construction. They may have some design guidelines but they cannot block you from building entirely.
What is the maximum size and height for an ADU in Los Angeles County?
Detached and attached ADUs can be built up to 1,200 square feet. JADUs are capped at 500 square feet and must be contained within the existing footprint of the primary home. For height, most detached ADUs in Los Angeles County are limited to 16 feet, though ADUs located above a garage or on a lot within half a mile of a major transit stop may be permitted up to 18 feet. If you are in the City of Los Angeles, the ADU Bonus Program may open the door to additional flexibility beyond standard size and height limits. Every lot is different so we always recommend a property review before locking in your design.
Does LA County require in-person submission of plans for an ADU?
No, most of everything can be submitted electronically.
Does LA County require a soils report for an ADU?
It depends on your project and location. Detached ADUs that are new construction may require a soils report, especially on hillside lots, lots with expansive soil conditions, or in areas with known geological concerns. Garage conversions and interior conversions typically do not require one. At Winter Remodeling Inc. we assess this during the planning phase so there are no surprise costs down the road.
