Zoning
All properties zoned for residential use may be eligible to build ADUs, with the exclusion of:
- Environmental Safety- Residential (ES-R)
- Manufacturing (M)
- Mixed Manufacturing (MM)
- Mixed Use-Light Industrial (MU-LI)
- Unclassified (U)
- on a lot with frontage on a roadway with less than 26 feet in pavement width in the Hillside Overlay (H)
Types of ADUs
Berkeley defines different types of ADUs:
- Jr. ADU (JADU): interior conversion of existing livable space (e.g. bedroom or finished basement)
- Conversion ADU: interior conversion of existing non-habitable area (e.g. garages, carports, unfinished basements)
- Attached ADU: new construction attached to existing structure
- Detached ADU: new construction detached from existing structures
Number of units
The number of ADUs you’re able to build depends on how your lot is zoned:
- Lots zoned for single family use may add 1 ADU and1 Jr. ADU (JADU).
- Lots zoned for multi-family may add 2 new detached ADUs and at least one conversion ADU (interior conversion of existing building, but no more than 25% of the original number of units. (E.g. an apartment with 4 units may add 2 detached ADUs and 1 conversion ADU.)
Building size
The maximum ADU you can build depends on your zoning and ADU type:
- JADUs may reach a maximum of 500 sq. ft.
- Conversion ADUs can reach 850 sq. ft. for a studio / 1 bedroom, and 1,000 for a 2+ bedroom
- Attached ADUs can reach no more than 50% of the floor area of the existing dwelling
- Detached ADUs can reach 1,200 sq. ft.
Building height
Detached ADUs can reach a maximum height of 16 feet. Attached ADUs must comply with the height requirements of the applicable zoning district.
Basements
Existing unfinished basement space can be used for a conversion ADU.
Setbacks
Minimum setbacks of 4 feet from the side and rear lot lines, as well as 6 feet from any existing structures are required for detached ADUs.
Parking
No additional parking is required for ADUs. Even when converting a garage or carport, replacement parking is not required.
Owner-occupancy
Owner occupancy is not a requirement for permitting an ADU from January 1, 2020 until January 1, 2025. This is a great opportunity for rental property owners to increase their yields in a cost-effective way.
Rental
While long-term rentals are permitted for ADUs, short-term rentals (e.g. Airbnb for less than 30 days) are not permitted in Berkeley.
Fees
Impact fees are waived for ADUs less than 750 sq. ft. Utility and connection fees are waived for JADUs and conversion ADUs in single family properties.
Watch-outs
Do you have a utility easement over your property? Do you have special setbacks? Reach out to us and we’ll help you build a custom ADU to fit your unique property characteristics and local regulations!