Building an ADU in Glendale. Rules, costs, timeline.

What you can build in Glendale

Everything in this section is grounded in GMC § 30.34.080 and the City of Glendale Community Development Department’s ADU guidance (updated November 7, 2025), with state-law citations called out where they preempt or supplement the local rule. We won’t re-cite the local section on every line; assume it under each subsection unless we tell you otherwise.

Glendale’s ADU rules track the California state floor on most dimensional questions, with three local elements that shape a project on the ground: the city’s fire-zone overlay (more restrictive than the state baseline on hillside parcels), the historic-property visibility rule, and a Glendale Water and Power easement-clearance step that can determine where on the lot an ADU can physically go.

Number of units allowed

Single-family lots — the state-law § 66323 stack. Glendale’s published ADU guidance describes a single-family lot as eligible for one ADU plus one Junior ADU. California state law and the HCD ADU Handbook are more generous. Under the § 66323 stack, an eligible single-family lot can typically combine all three of the following on the same parcel, regardless of any narrower local language:

• One conversion ADU — built inside an existing accessory structure or existing primary-dwelling space (Gov. Code § 66323(a)(1)).
• One Junior ADU (JADU) — up to 500 sqft inside the primary dwelling’s existing walls (Gov. Code § 66333).
• One new detached Statewide Exemption ADU — up to 800 sqft, 16 ft in height, with 4-ft side and rear setbacks (Gov. Code § 66323(a)(4) & (b)).

That is up to three units per lot under state law. The HCD ADU Handbook confirms this stack and treats it as the governing rule for any single-family lot, even when the local guidance still describes the older 1-ADU-plus-1-JADU framing. Glendale’s narrower handout is preempted under Gov. Code § 66316. Before you formally submit your application, ask the assigned Glendale planner to confirm in writing that the full three-unit § 66323 stack applies to your lot — that gets the entitlement on record before plan check starts.

Multifamily lots. Glendale’s guidance for multifamily properties allows one conversion ADU from existing non-livable area (with up to a 25% conversion bonus, rounded down), plus up to eight new detached ADUs — capped at the number of existing primary units on site. The detached-ADU cap of eight matches the state-law floor under Gov. Code § 66323(c) as amended by California SB 1211 (effective January 1, 2025). On Glendale’s significant stock of multifamily parcels in South Glendale and along Brand and Central, this is a meaningful unlock.

Size limits

• ADU maximum: 1,000 sqft, subject to the underlying zone’s floor area ratio (FAR), maximum lot coverage, and minimum landscaping standards when the ADU exceeds 800 sqft.
• Attached ADU > 800 sqft: may not exceed 50 percent of the primary residence’s floor area — this often becomes the binding constraint on smaller primary dwellings.
• Bedroom requirement: ADUs over 850 sqft must include a second bedroom.
• Junior ADU: up to 500 sqft, built entirely inside the primary residence’s existing legally permitted walls (including an attached garage). Must include an efficiency kitchen, independent access, and its own sanitation facilities or shared facilities with the main house. Mirrors Gov. Code § 66333.
• Garage conversion: must be constructed within the existing permitted garage footprint.
• Statewide Exemption ADU floor: per Gov. Code § 66323, every eligible lot is entitled to at least one ADU of up to 800 sqft, 16 ft in height, with 4-ft side and rear setbacks, regardless of local development standards.

Setbacks

• Side and rear setbacks (ADU ≤ 800 sqft): 4 feet from interior property lines — matches the state-law floor in Gov. Code § 66314(d)(7).
• ADU > 800 sqft: the underlying base zone’s development standards apply (FAR, lot coverage, landscaping). On many Glendale R1 and R1R lots, this is the practical constraint that decides whether a 1,000 sqft unit fits.
• Front setback: governed by the underlying base zone — Glendale applies the prevailing residential-zone front-yard setback to ADUs.
• Conversion: no additional setback required when the ADU is built inside an existing permitted accessory structure or the primary dwelling’s existing footprint.

Maximum height

• Detached ADU — default: 16 feet. Matches the state-law floor in Gov. Code § 66321(b)(4)(A).
• Detached ADU — HQTA exception: on lots within one-half mile of a designated High Quality Transit Area (major transit stop or high-quality transit corridor under Public Resources Code §§ 21064.3 and 21155), the height may reach 18 ft to the top plate plus an additional 2 ft to accommodate a roof pitch matching the primary dwelling (effective 20 ft). Matches Gov. Code § 66321(b)(4)(B). The City provides a reference HQTA map; the applicant is responsible for verifying.
• Attached ADU: up to 25 feet and 2 stories. Matches the state-law floor in Gov. Code § 66321(b)(4)(D) for attached ADUs.
• Story cap: in no case is more than 2 stories allowed.
• Rooftop decks: not permitted on top of any ADU. Rooftop parapets are limited to 18 inches and count toward the overall height calculation.

What this means for design. Glendale is a 1-story detached-ADU market. The 16-foot default cap doesn’t fit a two-story detached unit, and the HQTA bonus (18 ft + 2 ft for roof pitch, effective 20 ft) still tops out under any realistic two-story envelope. The 25-foot attached-ADU envelope exists on paper, but it only opens up when the ADU is bolted onto the primary residence — a different product than a detached backyard build, with different site, structural, and design tradeoffs. CALI ADU’s Signature Homes are designed and sold as detached units, so the Glendale lineup is a 1-story story. Glendale’s transit footprint is large — the Glendale Metrolink station serves Downtown, Beeline routes run along Brand, Central, Verdugo, Glenoaks, and Pacific, and the city sits on multiple LA Metro bus corridors — so the HQTA height bonus is in play for more lots than in most LA County cities, even though it doesn’t unlock a second story. The rooftop-deck prohibition rules out a popular Westside upgrade, so design conversations stay focused on grade-level outdoor space.

Parking

• Default rule: one off-street parking space per ADU.
• Exemption framework — subsection (H)(4) mirrors Gov. Code § 66322. No on-site parking required when the ADU meets any of the following:
  • Within one-half mile walking distance of public transit.
  • Contained entirely within the existing primary residence or an existing accessory structure.
  • Studio with no separate bedroom.
  • On a lot subject to a residential permit parking program where the ADU occupant is not eligible for a permit.
  • Within one block of a car-share vehicle.
• Garage conversion: no replacement parking required for the primary dwelling when a garage is demolished or converted in conjunction with ADU construction (Gov. Code § 66314(d)(11)). This rule preempts any local replacement-parking expectation.

Lot coverage and FAR

For ADUs over 800 sqft, Glendale applies the underlying zone’s development standards — FAR, maximum lot coverage, minimum landscaping, and objective design standards. On smaller Glendale lots, this is the rule that decides whether you can stretch from 800 sqft to the 1,000 sqft cap. For ADUs at or below 800 sqft, Gov. Code § 66321(b)(3) preempts any local FAR, lot coverage, or open-space standard that would prevent construction of an 800 sqft unit with 4-foot side and rear setbacks and 16 feet of height. The Statewide Exemption ADU under § 66323 is the floor any eligible Glendale lot can rely on.

Owner-occupancy

For ADUs: owner-occupancy is not required in Glendale. Gov. Code § 66315 prohibits cities from requiring owner-occupancy for an ADU, full stop. Glendale complies.

For JADUs: GMC § 30.34.080(I) requires a recorded covenant restricting future sale, development, and use of the site — the standard JADU deed-restriction mechanic. However, effective January 1, 2026, California AB 1154 amended Gov. Code § 66333(b) to narrow the owner-occupancy mandate so that it applies only when the JADU shares sanitation facilities with the primary residence. A JADU with its own dedicated bathroom is no longer subject to owner-occupancy under state law. If Glendale’s standard covenant template has not been updated to reflect AB 1154, raise the shared-sanitation distinction during pre-submission review and ask for the covenant language to track the narrower state-law rule.

Impact fees

• Under 750 sqft: exempt from Glendale’s development impact fee of approximately $5,000. Mirrors Gov. Code § 66318.
• 750 sqft and above: the development impact fee applies, calculated proportionally. Verify the current fee schedule with the Glendale Building Division at (818) 548-3200 before locking in your final square footage.
• Design implication: a 749-sqft ADU shaves a meaningful five-figure line item off the fee schedule compared to a 1,000 sqft unit. The Westwood Signature Home (550 sqft) and Wilshire Signature Home (400 sqft) both sit well inside the exemption.

Permitting timeline

Per Gov. Code § 66317, an ADU or JADU application that is deemed complete must be approved or denied ministerially within 60 days. No design review hearing, no neighbor notice, no discretionary conditions. Real-world elapsed time from initial submission to permit issuance in Glendale typically runs 3 to 5 months because the 60-day clock starts only after the application is deemed complete, and most projects go through a correction cycle or two before that point. Lots in the Verdugo / Crescenta / San Rafael foothills, in a historic district, or flagged for a Glendale Water and Power easement conflict run longer because of the additional review layers covered below.

Permitting your ADU

Ministerial review, 60-day clock

Per Gov. Code § 66317, Glendale must approve or deny a complete ADU or JADU application ministerially within 60 days of the application being deemed complete. No design review hearing. No Planning Commission action. No neighbor notice. If your plans meet the objective standards in GMC § 30.34.080, the City must approve.

The 60-day clock is statutory. The real-world elapsed time is longer because most projects go through one or two correction cycles, and because Building Division plan check runs alongside Planning review. Expect approximately 3 to 5 months from initial submission to permit issuance in Glendale on a straightforward project — longer on lots in a fire-zone overlay, in a historic district, or with Glendale Water and Power easement conflicts.

Glendale Water and Power easement clearance

The City’s ADU guidance is explicit: it is critically important to check with Glendale Water and Power (GWP) before finalizing siting, including for garage conversions, to confirm that the ADU footprint does not conflict with utility easements. GWP maintains both water and electric infrastructure across the city; an easement conflict identified late can force a redesign or kill an entire site plan. We run this check before drawings advance past schematic.

Pre-approved Standard ADU Plan Program

Glendale operates a Pre-Approved ADU Plan Program through the Community Development Department. The first standard plan (a 1-story, 740 sqft, 1 BR / 1 BA layout by YD Group) is published on the City’s ADU page, with additional standard plans listed as coming soon. The program is designed to expedite Planning and Building review for applicants who choose to build a pre-approved plan unchanged. CALI ADU Signature Homes are not part of the City’s pre-approved program — they are architect-designed custom plans — but the pre-approved program tells you something useful about the size and configuration the City Planning Division considers straightforward.

Where to submit

Building permit applications for ADUs are submitted through the City’s online Self Service portal (glendaleca-energovweb.tylerhost.net) under the Building Combination (Single Family) — Accessory Dwelling Unit path for SFR projects, or the equivalent Multi-Family or Commercial pathway. Pre-submission planning meetings can be scheduled at glendaleca.gov/PlanningAppt. Planning/Zoning counter: (818) 548-2140. Building Division: (818) 548-3200.

Pre-submission review we recommend

A pre-submission meeting with the assigned planner confirms code compliance before you enter the fee-paid review queue, flags any fire-zone or historic-district overlay specific to your parcel, lines up the Glendale Water and Power easement check, and identifies the state-law preemption positions (SB 1211, AB 1154, § 66323 Statewide Exemption) you may need to assert. We do this on every Glendale project, and it materially reduces correction cycles.

Glendale historic-district ADU rules

Glendale has a meaningful number of historic-resource properties — individually designated landmarks listed on the Glendale Register, contributors within established historic district overlay zones (Brockmont Park, Adams Hill, Royal Boulevard, Cottage Grove, and others), and properties eligible for the state or national registers. The historic-property rule for ADUs is straightforward, but it materially shapes design.

Per the City’s November 2025 ADU guidance, for historic properties: any exterior changes to create an ADU shall not be visible from the public street and must not alter any defining historical characteristic, unless doing so would preclude development of the ADU. Consult with the City’s historic preservation staff before finalizing the site plan or exterior package.

What this means for design. On a historic property, the favored ADU configurations are typically (a) a detached unit sited behind the primary house and screened from the street by the primary’s mass or by mature landscaping, (b) a garage conversion that preserves the historic facade of the accessory structure, or (c) a rear addition / attached ADU that does not modify the street-facing elevation of the primary house. Modern flat-roof packages can read jarringly on a Craftsman or Spanish-Colonial-Revival contributor; CALI ADU’s Signature Home lineup includes traditional gable, Craftsman, and Spanish flat-roof exterior options that read sympathetic to Glendale’s historic-district contexts. Pre-submission review with the historic preservation planner is essential.

Renting your new ADU

Glendale’s rental rules for ADUs sit at the intersection of three local code chapters worth understanding before you build. The short version: Glendale ADUs are long-term rental assets, not short-term-rental assets, and they are not subject to the city’s just-cause eviction regime.

Short-term rentals are prohibited. Per GMC Title 5, Chapter 5.56, vacation rentals — rentals where no host lives on site during the guest’s stay — are a prohibited use in all zones throughout the city. The city’s parallel home-sharing ordinance (also in Chapter 5.56) only governs hosted rentals of 30 consecutive days or less. A stand-alone ADU rented to a tenant who is not co-living with the host is by definition a long-term rental: 30 days minimum, with monthly or year-long leases the norm.

Just-cause eviction does not apply. Per GMC Chapter 9.30, single-family dwellings, condominiums, townhouses, accessory dwelling units, government-subsidized units including Section 8, and parcels with only two units are exempt from the just-cause and retaliatory-eviction ordinance in its entirety. The one-year written-lease offer requirement and the 7% / 12-month rent-increase relocation benefits trigger that apply to covered Glendale rental housing do not apply to your ADU on a single-family lot.

A few drivers anchor Glendale rental demand. Downtown Glendale’s job density (DreamWorks Animation in Glendale, Disney’s Grand Central Creative Campus, and a substantial professional-services and finance employer base), the Glendale Galleria and Americana retail and dining anchors, and Glendale Adventist Medical Center all pull steady rental demand. The city’s tight rental supply and walkable Brand Boulevard corridor support competitive 1- and 2-bedroom ADU rents. A well-finished unit in Glendale typically leases within 60 to 90 days of completion. A rough payback on the all-in build is 10 to 14 years at 2026 Glendale rents. The exact number turns on which Signature Home you build and the lot you build it on.