Accessory Dwelling Units

Welcome to the City of Laguna Niguel ADU webpage! In an effort to accelerate housing construction throughout California, the State legislature passed a series of laws to encourage Accessory Dwelling Units (ADUs) in single and multi-family neighborhoods. Accessory Dwelling Units (ADUs) and Junior Accessory Dwelling Units (JADUs) are independent living facilities located on the same parcel as the primary unit, which may be occupied by extended family members or tenants.

The City's ADU Ordinance (Ordinance No. 2021-211) is consistent with State law while maintaining the fabric of our community. Below is more information about Accessory Dwelling Units and Junior Accessory Dwelling Units. For questions, please contact (949) 362-4300 or email

ADU Handout 2 Reduced

Please refer to the Laguna Niguel ADU Handbook below for information on building an ADU or JADU, including development standards, requirements, and a submittal checklist.

Example ADU Floor Plans and Renderings - PDF Files

The sample floor plans are available below as CAD files for architects and designers.

Example ADU Floor Plans - CAD Files

Floor Plan Rendering Resized

Frequently Asked Questions

1. Why do people build ADUs and JADUs?

Homeowners build ADUs for many reasons. A few of the most common reasons we hear from property owners are listed below:

  • Passive income from rental property or retirement income.
  • Increased property value and long-term investment.
  • Long-term family or guest accommodations.
  • Home additions.

2. How many ADUs can be built on my property?

Single-family residences are permitted to have one ADU and one JADU per lot. To learn about the difference between these two types of ADUs, please refer to the ADU handout provided in the link above.

3. How does an ADU impact my property taxes?

The construction of an ADU does not trigger a complete reassessment of the value of your home. Instead, the county tax assessor will do a “blended assessment” of your property. In a “blended assessment”, the assessor estimates the value of the ADU based on the cost of building the ADU. The assessor adds this number to the current assessed value of the property in order to create a new assessed property value. The value of the primary home is not reassessed.

Once an ADU project is completed, your property taxes will only increase based on the additional value created by your ADU. The taxes you pay on the primary home will not change.

4. Is short-term lodging allowed in ADUs?

Short-term lodging is prohibited. Units are not to be rented for less than 30 days.

5. Are there any grant programs for ADUs?

Yes! The California Housing Finance Agency ADU Grant program provides up to $40,000 towards pre-development and non-reoccurring closing costs associated with the construction of the ADU. Predevelopment costs include site prep, architectural designs, permits, soil tests, impact fees, property surveys, and energy reports. For more information, please visit the California Housing Finance Agency ADU Program webpage.