TranslateDifferences Among ADUs, JADUs, and Guest Houses
Sonoma County allows several types of residential accessory structures (see Policy 1-4-6, Residential Accessory Structures for a complete list). Below is a summary of the differences among a few of the most common residential accessory structures: Accessory Dwelling Units (ADUs), Junior Accessory Dwelling Units (JADUs), and guest houses.
| Structure Type | Accessory Dwelling Unit | Junior Accessory Dwelling Unit | Guest House |
|---|---|---|---|
| Structure | May be attached to or detached from the main dwelling or accessory structure | Must be created from, and within the footprint of, an existing or proposed single-family dwelling | Accessory building to a single-family dwelling which consists of a detached living area of a permanent type of construction |
| Kitchen | Must have a full kitchen (see Policy 1-4-5, Definition of a Kitchen) | Must have a small kitchen | Cannot have a kitchen or wet bar |
| Bathroom | Must have a full bathroom | Must have direct access to a bathroom, either inside the unit or in the main house | May have a half or full bath |
| Long-Term Rental | Can be rented | Can be rented | Cannot be rented or occupied separately from the main house |
| Transient Rental | May not be used as a vacation rental | May not be used as a vacation rental | May be able to be used as part of a vacation rental or hosted rental with a zoning permit |
| Z Combining District | Prohibited in the Z Combining District | Allowed in the Z Combining District | Allowed in the Z Combining District |
| Size Limit | 1,200 square feet | 500 square feet | 640 square feet |
| Permits Required | Building permit | Building permit | Building permit |
| More Information | Accessory Dwelling Units | Junior Accessory Dwelling Units | 1-4-6 Detached Residential Accessory Structures |
| Zoning Code Reference |
Section 26-88-060 of the Sonoma County Zoning Ordinance. See the County’s ADU website for more information and resources. |
Section 26-88-061 of the Sonoma County Zoning Ordinance. See the County’s JADU website for more information and resources. |
"Guest house" Ordinance No. 6335, 26-4-020, Section G-6 |