Single-Family ADU

ADU Types

An accessory dwelling unit or junior accessory dwelling unit can be permitted if located on a lot zoned for residential use (including residential mixed-use) where only one residential dwelling unit exists or is proposed to be built on a lot, provided the applicant builds under either subparagraph (1) or (2) below, but not both:

  1. One accessory dwelling unit or junior accessory dwelling unit shall be allowed when all of the following apply:

a. An accessory dwelling unit shall be located within the proposed or existing space of a single-family dwelling or existing space of an accessory structure and may include an expansion of an accessory building not to exceed 150 square feet beyond the physical dimensions of the existing accessory building. An expansion beyond the physical dimension of the existing accessory building shall be limited to accommodating ingress and egress:

b. The space has exterior access from the proposed or existing single-family dwelling

c. No setback shall be required for an existing structure, or portion thereof, that is converted to an accessory dwelling unit unless it is required to provide sufficient fire safety and

d. The junior accessory dwelling unit complies with all other junior accessory dwelling unit requirements in this document.

2. One detached, new construction, accessory dwelling unit shall be allowed. This provision may be combined to allow a junior accessory dwelling unit in the manner described in the subparagraph (a) above only where one residential dwelling unit exists, or is proposed to be constructed at the same time as the accessory dwelling unit and junior accessory dwelling unit and subject to:

a. A minimum four-foot side and rear setback

b. A maximum square footage of 800 square feet

c. A height limit of 16 feet

3. Single-Family Zoned Lots with Two Detached Single-Family Units

    1. One (1) accessory dwelling unit or one (1) junior accessory dwelling unit is permitted per lot
      1. One (1) junior accessory dwelling unit may be combined with one (1) detached, accessory dwelling unit

Development Standards

1. CONVERTED ACCESSORY DWELLING UNITS.

a. Unit Size.

i. Minimum unit size: None

ii. Maximum unit size: None

b. Setback Requirements. No setbacks shall be required for an existing living area or accessory structure converted to an accessory dwelling unit, or a new structure reconstructed in the same location and to the same dimension as an existing structure unless it is required to provide sufficient fire safety.

c. Building Separation. No minimum building separation requirement.

d. Separate Access. An accessory dwelling unit shall provide separate exterior access from the existing primary residence. Entry doors cannot be on the same façade as the entry door of the primary residence, unless this requirement prevents creation of the accessory dwelling unit.

e. Windows and Doors for Historic Properties. Windows and doors (including opening and garage doors) for historic properties that are original to the structure are required to be retained, unless this requirement prevents creation of the accessory dwelling unit.

2. NEWLY CONSTRUCTED ACCESSORY DWELLING UNITS.

a. Unit Size.

i. Minimum unit size: No less than 150 square feet in size

ii. Maximum unit size:

a) For parcels less than 10,000 square feet in size: All newly constructed, detached accessory dwelling units shall not exceed 850 square feet, except for an accessory dwelling unit that provides more than one bedroom the accessory dwelling unit shall not exceed 1,000 square feet.

b) For parcels equal to or greater than 10,000 square feet in size: All newly constructed, detached accessory dwelling units shall not exceed 850 square feet, except for an accessory dwelling unit that provides more than one bedroom the accessory dwelling unit shall not exceed 1,200 square feet.

c) When a newly constructed accessory dwelling unit is attached to the existing primary dwelling unit, the maximum allowed size of that accessory dwelling unit shall be no more than 50% of the main dwelling size or 800 square feet, whichever is greater.

b. Site Planning. A detached accessory dwelling unit shall be located behind the rear building line of the primary residence, and be clearly subordinate by location and size, so long as it does not prohibit an accessory dwelling unit of at least 800 square feet.

c. Setback Requirement. The minimum required setback shall comply with Section 17.22.040, with the following exceptions:

Side (Corner & Interior) Setback Rear Setback
ADU ≤ 800 SF 4 ft 4 ft
ADU > 800 SF 10% of lot width
(min. 5 ft, max. 10 ft)
10 ft
ADU constructed on top of an attached garage 5 ft 5 ft

 

d. Building Separation. A minimum building separation of six feet shall be maintained (eave to eave) between the primary residence and detached accessory dwelling unit.

e. Maximum Height. A newly constructed, detached accessory dwelling unit shall be limited to a height of one story, not to exceed 12 feet to the top plate and 17 feet to the highest ridgeline.

i. Exception. A newly constructed attached accessory dwelling unit may extend to a height of two stories, per the maximum allowed height in Section 17.22.040, if the existing primary residence is two stories in height.

3. ADDITIONAL STANDARDS. An applicant shall be entitled to develop an accessory dwelling unit that is 800 square feet or less in size provided the accessory dwelling unit provides four-foot minimum side and rear setbacks and does not exceed 16 feet in height regardless of the development standards for floor area ratio, lot coverage, and open space set forth in Title 17 of the Pasadena Municipal Code.