An accessory dwelling unit, or ADU, is a residential unit that can be added to a lot with an existing single family home. A California law (AB 2299) makes it easier for homeowners to build these small residences to address the State’s housing shortage. Many cities have set ADU standards that may differ from the details below. This information is based on the standards set for ADUs in Glendale, CA.
Building an ADU is costly, and may not be the best choice for your needs. Check out these 14 things you need to know about ADUs before you build one. If you decide to move forward with your ADU dreams, we know some experts that can help you out.
1. Is my property eligible for an ADU?
ADUs can only be built on sites with one dwelling unit, such as a single family home.
2. Where can I locate it?
An ADU can be a new addition, attached to the primary house or separate from the house. You may convert existing floor area into an ADU, or convert a garage. If you convert your garage into an ADU you will need to replace the parking spaces on your property.
3. What size can it be?
Your Glendale, CA ADU can be between 150 and 600 square feet.
4. What must it include?
A bathroom, a kitchen, an independent entrance and service from utilities including sewer, water and electric must be included in your ADU.
5. How much is this going to cost me?
Permit fees are approximately $9,000-$13,000 based on building valuation and type of construction.
Covenant fees cost $2,350. A covenant is a legal document that will tie the primary house to the ADU.
Construction fees depend on how fancy you want to get with your materials and other special considerations. Talk to your favorite contractor to get an idea of how much you will need to pay to build your accessory dwelling unit.
6. What are the parking requirements?
One parking space is required for an ADU unless one or more conditions applies to your property: The property is located within 1/2 a mile radius of a public bus or train stop. The property is located within a historically significant district. The ADU is part of an existing primary residence.
7. Do I have to install fire sprinklers?
It depends. Check with Building & Safety for specifics.
8. Will it have a separate address?
Yes, the ADU will have its own separate address.
9. What about utilities?
Separate water and electric meters are not required for your ADU. If you would like separate bills, however, you’ll need to get a separate meter.
10. What development standards apply?
ADUs are subject to all relevant zoning regulations including maximum floor area and lot coverage.
11. Can I rent it?
The owner of the property must live in either the ADU or the primary residence, or the entire property must be rented as one. Short term rentals are not allowed.
12. Can I sell it?
No, you can only sell your house and ADU together. A covenant and agreement must be recorded (see #5) to prevent separate sale.
13. What about the design of my ADU?
ADUs must be architecturally compatible with the existing primary structure.
14. Will it affect future additions?
If you are planning on adding on to your primary residence floor plan, it needs to be completed before any garage conversion to an ADU, because an addition of any new floor area requires all required parking to be provided.
Click here for the complete, printable brochure from the City of Glendale that highlights the basics of ADUs.