Understanding Municipal Boundaries: City of Pasadena vs. Surrounding Areas

Before reviewing zoning rules, verify that your parcel lies within the incorporated City of Pasadena. Southern California municipal borders often intertwine, but building departments do not:

  • City of Pasadena (This Guide): Governed by the Pasadena Municipal Code (PMC Title 17) and processed through the Pasadena Permit Center / Planning & Community Development Department.
  • City of South Pasadena (Distinct): An independent incorporated municipality with its own separate zoning code, city council, and building department.
  • City of Los Angeles (Distinct): Governed by the Los Angeles Municipal Code (LAMC) and the Los Angeles Department of Building and Safety (LADBS).
  • Unincorporated Los Angeles County (Distinct): Communities bordering Pasadena (such as parts of Altadena or East Pasadena) are governed by the Los Angeles County Department of Regional Planning (DRP) and LA County Public Works, not City of Pasadena municipal offices.

If your property is located in the incorporated City of Pasadena, the following municipal standards apply to your parcel. Zoning staff confirm the rules that apply to your specific address — a quick check before design starts can save a redesign.

How Many ADUs Can You Build on Your Pasadena Property?

Pasadena zoning accommodates accessory dwelling units on both single-family and multifamily residential parcels, under state law (Gov. Code §§ 66310–66342) and Pasadena Municipal Code § 17.50.275 (as amended through Ordinance No. 7471).

Single-Family Residential Lots

Homeowners with an existing or proposed single-family dwelling may combine up to three accessory units: 1. One new-construction ADU: Built new, either detached in the yard or attached to the home. 2. One converted ADU: Created within existing space — such as a garage, carriage house, pool house, or similar accessory structure (or within the home itself). Conversions of an accessory structure may expand by up to 150 square feet, limited to accommodating ingress and egress. 3. One Junior Accessory Dwelling Unit (JADU): Limited to 500 square feet, built entirely within the walls of the existing or proposed single-family residence (including an attached garage), with its own exterior entrance.

An "exemption ADU" — a new-construction unit of up to 800 square feet with four-foot side and rear setbacks (and a four-foot front setback) — receives the state's most streamlined ministerial review, with no parking required and no additional zone development standards applied.

Multifamily Residential Properties

Owners of lots with existing or proposed multifamily dwellings (two or more attached units) have two distinct pathways: - Converted ADUs (within existing non-livable space): At least one ADU must be allowed, and up to 25% of the existing multifamily dwelling units, created within spaces not used as livable space — storage rooms, boiler rooms, passageways, attics, basements, or garages. - Detached new-construction ADUs: On a lot with an existing multifamily dwelling, up to eight detached ADUs (not more than the number of existing units on the lot). On a lot with a proposed multifamily dwelling, up to two detached ADUs. Detached units on multifamily lots use four-foot side and rear setbacks.

Maximum Size Allowances for Pasadena ADUs

The allowable square footage depends on unit type, lot configuration, and whether the unit qualifies as an "exemption ADU" under state law:

ADU Configuration Maximum Size Key Requirements
Exemption ADU (new construction, attached or detached) Up to 800 sq. ft. Four-foot side, rear, and front setbacks; ministerial approval; no parking required
Detached ADU, new construction (single-family) Up to 1,200 sq. ft. Reduced to 1,000 sq. ft. in most Hillside Overlay areas, and to 800 sq. ft. on hillside streets with pavement 26 feet wide or narrower
Attached ADU, new construction 850 sq. ft. (studio or 1-bedroom); 1,000 sq. ft. (2+ bedrooms) State law also caps attached ADUs at 50% of the existing primary dwelling's floor area for ordinance-based units
Conversion ADU (attached or detached) No size limit Plus up to 150 sq. ft. of expansion for ingress/egress only
Junior ADU (JADU) 500 sq. ft. Within the walls of the primary residence, including an attached garage
Detached ADU (multifamily lot) Per state exemptions; height and setback standards apply See unit counts above

Every ADU must be at least 150 square feet. Applicants may choose whether floor area is measured under the Zoning Code or the California Building Code — worth confirming with your designer if your project sits near a threshold.

Note on fees: on single-family sites, Pasadena exempts ADUs of 900 square feet or less from its Residential Impact Fees (RIF) — a local threshold more generous than the state's 750-square-foot fee exemption. See the FAQ below for the full fee picture.

Setback Requirements & Building Separation

Setbacks ensure adequate emergency egress, fire separation, privacy, and utility clearance between neighboring parcels.

  • Side & Rear Setbacks (New Construction): A minimum of 4 feet from side and rear property lines is required for newly constructed ADUs and for expansions to conversion ADUs.
  • Conversions of Existing Structures: Converting an existing legal structure into an ADU requires no additional setbacks beyond fire-safety needs. If an existing structure is demolished and rebuilt in the same location with the same dimensions and height, no setbacks are required except for fire safety.
  • Front Yard Setbacks: New-construction ADUs larger than 800 square feet must comply with the underlying zone's front-yard setback. State law prohibits using front-setback rules to prevent an 800-square-foot ADU with four-foot side and rear setbacks from being built, and Pasadena permits exemption ADUs with a four-foot front setback.
  • Building Separation: For non-exemption ADUs, a minimum building separation of six feet (eave to eave) is required between a newly constructed ADU and any other structure on the site (excluding walls and fences).

Building Heights & Stories

Height limits depend on unit type, site conditions, and location:

  • Detached New-Construction ADU (single-family): Standard maximum of 18 feet and two stories. A lower 16-foot cap applies within Hillside Overlay Districts, within Landmark or Historic Districts where the unit is visible from the street, and for exemption ADUs located in the front-yard setback — but those same units return to 18 feet if the site has an existing or proposed multistory building or lies within one-half mile walking distance of a Major Transit Stop or High Quality Transit Corridor.
  • Roof Pitch Allowance: On sites within one-half mile walking distance of a Major Transit Stop or High Quality Transit Corridor, an additional two feet of height is permitted where necessary to match the roof pitch of the primary dwelling.
  • Attached ADU: Maximum 25 feet or the height limit of the underlying zone, whichever is lower, and up to two stories.
  • Detached ADUs (multifamily lots): Maximum 16 feet, rising to 18 feet if the multifamily building is multistory or the lot is near a Major Transit Stop or High Quality Transit Corridor (plus two feet for roof pitch matching near transit).
  • Conversions: Converted structures keep their existing legal height and dimensions.
  • Applicant's Choice of Measurement: Pasadena lets the applicant choose whether height (and floor area) is measured under the Zoning Code or the California Building Code — a detail that can decide close cases.

Parking Rules and Transit Exemptions

When is Off-Street Parking Required?

Pasadena’s adopted Ordinance No. 7471 states one parking space per ADU on a single-family site, unless an exemption applies, and no parking requirement for ADUs on multifamily sites. The City’s ADU webpage still uses a different formula: “one parking space per unit or per bedroom, whichever is less.” Confirm the requirement for your proposed unit with the Permit Center before finalizing the site plan. Where parking is required, the ordinance allows a covered or uncovered space, or tandem parking on an existing driveway; the ADU shares the existing driveway with the primary residence.

When are You Exempt from Adding Parking?

No parking space is required for a single-family ADU if any of the following apply: 1. The unit is an Exemption ADU (up to 800 sq. ft., four-foot setbacks). 2. The site is within one-half mile walking distance of a public transit stop. 3. The ADU is contained within the proposed or existing enclosed space of the primary dwelling or accessory structure, as described in the ordinance. 4. The property is within a historic district (including landmark and historic districts). 5. A commercial car-share vehicle pick-up and drop-off location is within one block of the ADU. 6. The ADU application is submitted with an application for a new single-family dwelling on the same lot, and the ADU meets one of the transit, enclosed-space, historic-district or car-share criteria above.

State law adds a further exemption where on-street parking permits are required but not offered to the ADU's occupant.

Garage Demolition or Conversion

Under Ordinance No. 7471, replacement parking is not required when an existing garage, carport or surface space serving as required parking for the primary dwelling is demolished or converted in conjunction with ADU construction or conversion.

Special Pasadena Requirements: Historic Districts, Energy Codes, Utilities & Rentals

Historic Districts & Landmark Properties

Pasadena is home to numerous recognized historic and landmark districts (such as Bungalow Heaven and Garfield Heights). In these zones: - New non-exemption ADUs on individually designated historic properties or within Landmark or Historic Districts must not be visible from the public right-of-way, unless that requirement would prevent the unit from being created. - Design review by Pasadena Design & Historic Preservation staff may apply. Confirm requirements early if your property is designated or within a district.

Building Electrification: ADUs Are Exempt

Pasadena's building electrification ordinance (Ordinance No. 7398, adopted August 2022) requires all-electric construction for certain new multifamily (four or more units), mixed-use, and commercial buildings. It does not require ADUs or JADUs to be all-electric: newly constructed, added, or converted ADUs and JADUs on single-family or multifamily properties are expressly exempt. The City has also announced that enforcement of Ordinance No. 7398 is suspended (per the City's notice effective August 20, 2025). Because the City's implementation status can change, confirm current requirements with the Permit Center before finalizing mechanical, electrical, or plumbing design.

Solar (Title 24) Requirements

Permit applications submitted on or after January 1, 2026 must comply with the 2025 California Energy Code (Title 24, Part 6). Newly constructed detached ADUs generally require a photovoltaic (solar) system, subject to applicable exceptions. The new-construction PV requirement does not apply to additions or alterations; your project’s classification matters. Have your Title 24 consultant document the applicable solar, equipment and readiness requirements, along with any claimed exception. Performance modeling is not a blanket exemption from solar, and converting existing space does not remove all energy-code obligations.

Water, Power, and Utility Metering

  • Standalone electric or water meters are not mandated by the City; the ADU may share service with the primary dwelling.
  • Separate meters may be requested directly through Pasadena Water & Power (PWP) if independent tenant utility billing is desired.
  • Fire department access and water flow must be verified during plan check. Fire sprinklers are not required in the ADU if sprinklers are not required for the primary residence, and building an ADU does not trigger sprinkler requirements for the existing home.

Rental Guidelines & Short-Term Rental Limitations

  • Long-Term Rentals: ADUs may be rented as independent residential housing. For ADUs legally created on or after January 1, 2017, Pasadena requires any rental term to be longer than 30 days — short-term vacation rentals of these units are not permitted.
  • Sale of Units: An ADU or JADU generally cannot be sold separately from the primary residence (narrow statutory exceptions apply, such as qualified nonprofit ownership transfers).

The Pasadena ADU Permitting Process: Step by Step

Permitting an ADU involves structured technical coordination between property owners, designers, and municipal plan examiners:

Step 1: Feasibility & Zoning Check Confirm parcel boundaries, underlying zoning district, utility easements, and overlay zones (Historic or Hillside). │ ▼ Step 2: Architectural & Structural Drafting Prepare site plans, floor plans, elevations, Title 24 energy calculations, and structural framing notes. │ ▼ Step 3: Online Submittal via Pasadena's Permit Portal Submit electronic plans through the City's online permit portal (cityofpasadena.net/mypermits). │ ▼ Step 4: Departmental Plan Check Review Plans undergo multi-department review: Planning & Zoning, Building & Safety, Fire, Public Works, and Pasadena Water & Power. │ ▼ Step 5: Plan Corrections & Clearance Incorporate plan check comments, submit revised plan sheets, pay remaining permit fees, and receive issued permits.

Turnaround times depend on submittal completeness, plan complexity, and current municipal review queues. Under California law, the City must determine whether an ADU application is complete within 15 business days, and must approve or deny a completed application within 60 days for lots with an existing dwelling — if the City does not act within 60 days, the application is deemed approved. Review is ministerial: no discretionary hearings for code-compliant ADUs.

Frequently Asked Questions About Pasadena ADUs

Do I need to submit plans in person at the Pasadena Permit Center?

No. The City of Pasadena accepts electronic plan submittals online through its permit portal at cityofpasadena.net/mypermits.

Does building an ADU in Pasadena require a soils report?

Not for every parcel. Additional geotechnical documentation is most likely to come into play on hillside lots or where structural conditions warrant it. The Permit Center can confirm whether your specific parcel requires a soils investigation before you commission one.

What is the Pasadena Residential Impact Fee (RIF), and who pays it?

Pasadena assesses a Residential Impact Fee to support community infrastructure. The current rules are favorable to most homeowners: - ADUs of 900 square feet or less on single-family sites are exempt from the RIF. - ADUs of any size with an executed Pasadena Housing Agreement (an ADU Affordability Covenant or Landlord Agreement) are also RIF-exempt, with additional fee discounts. - ADUs greater than 900 square feet without a Housing Agreement pay a proportional RIF. - Statewide, California law prohibits impact fees on ADUs of 750 square feet or less, so the state floor protects smaller units everywhere. - Note: these local fee reductions apply to single-family sites and are not retroactive; multifamily sites do not qualify.

Does an ADU receive its own street address in Pasadena?

Address assignment for a newly permitted ADU is handled through the City's permitting process, and separate addressing helps emergency dispatch when a unit has its own entrance. Confirm addressing details and any associated fees with the Permit Center when you apply.

Can I build a two-story ADU in Pasadena?

Yes. Detached ADUs may reach two stories within the standard 18-foot height limit (16 feet in Hillside Overlay or street-visible historic settings, with transit/multistory exceptions back up to 18 feet, plus two feet for roof pitch matching near transit). Attached ADUs may be up to two stories within the 25-foot (or underlying zone) cap. Mind the second-story window rule: for non-exemption ADUs, new second-story windows are not permitted on interior side or rear walls set back less than five feet, unless the Building Code requires them (as clerestory windows).

Plan Your Pasadena ADU with Go ADU Construction

Every property in Pasadena brings its own parcel dimensions, setback geometry, overlay questions, and utility conditions. Go ADU Construction builds ADUs in Pasadena and works with homeowners to plan around the City's current requirements — from early feasibility through permitting and construction.

Connect with our Pasadena project team to discuss your property's potential:

Discuss Your Pasadena ADU Project

Explore our local construction capabilities, completed project profiles, and Pasadena neighborhood coverage on our Pasadena Service Area Page.