Accessory Dwelling Units (ADUs) are residential units that can be added to single-family homes in California, providing additional living space for various needs and generating rental income. State laws encourage ADU construction by streamlining approval processes and limiting local regulations on size, parking, and utility fees. Local guidelines vary; for instance, Glendale allows a maximum 500 square feet, while Los Angeles permits up to 1,200 square feet without a homeowner covenant.

1. ACCESSORY
DWELLING UNITS
State of California
Glendale
La Canada Flintridge
La Crescenta (Unincorporated LA County)
City of Los Angeles
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2. What is an ADU?
•An Accessory Dwelling Unit (ADU) is a residential unit
that can be added to a lot with an existing single family
home.
•ADUs can be detached (a separate building in a
backyard), attached to or part of the primary residence,
or a garage conversion.
•ADUs are independent rental units that have their own
kitchens, bathrooms, living areas, and entrances.
•ADU housing units go by many names: backyard
homes, secondary units, garage apartments.
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3. Why Build an ADU?
•ADUs can provide additional space for:
•Caregivers
•Grown children
•Elderly parents
•Renters
•Because ADUs are rental units, they produce additional
household income.
•“Empty nesters” can stay in their neighborhoods by
moving into a smaller ADU and renting their larger
existing home to pay the mortgage.
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4. What is the State Law for ADUs?
•In January of 2017, a new California state law (AB 2299)
took effect that encourages homeowners to build
ADUs.
•Local governments must ministerially approve one ADU
per single family lot if the unit is:
•contained within an existing residence or accessory
structure.
•has independent exterior access from the existing
residence.
•has side and rear setbacks that are sufficient for fire
safety (garage conversions are “grandfathered”).
•Prohibits a local government from adopting an
ordinance that precludes ADUs.
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5. Parking Requirements
•One space per bedroom or unit.
•Off street parking may be tandem or in setback areas.
•No parking requirements if the ADU meets any of the
following:
•Is within a half mile from public transit.
•Is within an architecturally and historically significant
historic district.
•Is part of an existing primary residence or an existing
accessory structure.
•Is in an area where on-street parking permits are
required, but not offered to the occupant of the ADU.
•Is located within one block of a car share area.
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6. ADU Size and Setbacks
• Attached ADUs are limited to a maximum of 50% of the
existing living area, with a maximum increase in floor area of
1,200 square feet (excluding garage).
• Detached ADUs are limited to a maximum of 1,200 square
feet (excluding garage).
• For ADUs that require an addition or a new accessory
detached structure, more restrictive maximum ADU size can
be established by local jurisdictions with certain limitations.
• Underlying FAR and lot coverage restrictions may restrict
maximum ADU size allowed.
• No passageway can be required.
• No additional setback can be required from an existing
garage that is converted to an ADU.
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7. Fees
•ADUs shall not be considered new residential uses for
the purpose of calculating utility connection fees or
capacity charges, including water and sewer service.
•State law prohibits a local agency from requiring an
ADU applicant to install a new or separate utility
connection or impose a related connection fee or
capacity charge forADUs that are contained within an
existing residence or accessory structure.
•For attached and detached ADUs, this fee or charge
must be proportionate to the burden of the unit on the
water or sewer system and may not exceed the
reasonable cost of providing the service.
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8. Glendale
•Interim ordinance expires 2-8-18
•500 sf max ADU size
•Homeowner covenant required
•The property owner shall pay all sewer, water, school
district, and other applicable fees, including development
impact fees (reduced from $21K to $4.7K).
•The property owner shall install a new or separate utility
connection between the ADU and the utility, and pay all
applicable connection fees or capacity charges, except if
the ADU is within existing residence/accessory space.
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9. La Canada Flintridge
• Not allowed on lots under 10,000 sf
• Homeowner covenant required
• The accessory dwelling unit must be connected
with the primary dwelling unit to common utility
meters, including gas, electricity and water© 2018 amk STUDIO

10. La Canada Flintridge
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11. La Crescenta (Unincorporated LA County)
•Revisions to ordinance to be considered on 1-24-18
•1200 sf max ADU size
•No parking required forADU
•No homeowner covenant proposed
•No development impact fees
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12. City of Los Angeles
•1200 sf max ADU size
•No homeowner covenant required
•Excellent handbook “Building an ADU Guidebook to
Accessory Dwelling Units in the city of Los Angeles”
available online in partnership with UCLA.
•Guidebook does not replace services of professional
designers, but it does provide helpful advice, websites,
phone numbers, and office locations.
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13. ADU Design Process
1. Take photos of your property
2. Make a sketch of existing home and proposed
ADU design concept.
3. Take your photos and sketch and meet with
Building Department to confirm that your
proposedADU meets local requirements.
4. Secure financing based on estimated project costs
including design, permitting fees, and
construction.
5. Hire design team to finalize design concept and
draw floorplans, elevations, and related
construction documents.
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14. ADU Permitting Process
1. Submit construction drawings to Building
Department for plan check review (may require
revisions to construction drawings).
2. Pay building permit fees, utility interconnection
charges, and applicable development impact fees.
3. Building permit issued.
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15. ADU Construction Process
1. Obtain bids from at least three contractors.
2. Select contractor.
3. Begin construction.
4. Construction inspection by building field inspector
(may require revisions to approved construction
drawings).
5. Certificate of Occupancy.
6. Host Housewarming Party!
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16. DISCUSSION
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17. DETACHED (corner lot)
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18. DETACHED (corner lot)
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19. DETACHED (front unit)
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20. DETACHED… (front unit)© 2018 amk STUDIO

21. DETACHED- (over garage)
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22. DETACHED- (over garage)
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23. LOT SPLIT – SMALL LOT ORDINANCE
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24. THANKYOU!
For More Info:
Javier Mariscal, AICP, LEED GA
at AMK Studio Architecture
(818) 429-4066 call/text
jmariscal@amkstudio.com
Arlene Edjourian, AIA, NCARB, LeedAP
at AMK Studio Architecture
& GMD Design Group of CA, Inc
(949) 863-3000
aedjourian@amkstudio.com
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