Overview of ADU Regulations
Accessory dwelling units (ADUs) are allowed on any parcel where the zoning district or General Plan allows residential uses, and there is an existing or proposed primary dwelling. ADUs can be attached or detached from the primary dwelling, new construction or converted from existing space, and can be standard or junior ADUs. For more information see Types of ADUs.
State Laws in Effect January 2020
Number of ADUs Allowed
Permitting, planning and other fees vary with ADU type and parcel location. To the extent fees are based on size of the unit, number of bedrooms or project valuation, ADU design can influence fee costs. See the Financing Guide and the Fee, Cost and Cash Flow Estimator for more information. Certain fees are waived or reduced for ADUs as follows:
- Reduced building permit fees for Conversion ADUs.
- Waiver of sewer and water connection fees for JADUs and Conversion ADUs
- Waiver of Planning Department permit fees for ADUs ≤ 640 sf
- Waiver of impact fees for ADUs less than 750 sf. Impact fees for larger ADUs are proportional to square footage.
- Waiver of transportation and roads fees when no parking is required for ADU.
- Waiver of Affordable Housing Impact fee for Conversion ADUs
Alternatives to ADUs