ADU Builder in Azusa, CA: Permits, Pre-Approved Plans and Costs

What local rules apply to building an ADU in Azusa?

Azusa's ADU rules are codified in the city's municipal code and were most recently amended by Ordinance 2024-08. The city lists three pre-approved plans on its Planning Division page: an 800 sq ft 2-bed/2-bath design and two 1,000 sq ft 3-bed/2-bath designs, all submitted by Aligcus Construction. One ADU and one JADU are allowed per single-family lot. A detached ADU may not exceed 1,200 sq ft under the Building Division submittal handout, and an attached ADU is capped at 50% of the existing dwelling area (excluding garage) and 1,200 sq ft. A JADU is limited to 500 sq ft and must be owner occupied. State law still binds the city where the local rule is silent: a detached ADU is hard-capped at 1,200 sq ft under Section 66314(d)(5), and side and rear setbacks for an ADU are capped at 4 ft under Section 66314(d)(7).

How long does the Azusa ADU permit process take?

Submittal goes to the Building Division by email for a preliminary completeness review. Under Section 66317(a)(2), the city has 15 business days from submittal to decide whether the application is complete. Once the application is complete, the city has 60 days under Section 66317(a)(3) to approve or deny it. If the city misses the 60 day clock without an applicant-requested delay, the application is deemed approved. The plan check fee schedule is published on the city's Planning Division site, and an online fee estimator handles plan check, permit, and certain development fees. For a project located inside a mapped High Fire Hazard Severity Zone, the Los Angeles County Fire Department reviews the construction plans under Chapter 7A wildfire construction standards before permit issuance.

How much does an ADU cost in Azusa?

Typical L Square ADU packages start at $180,000 for the smallest prefab model and go up through $240,000, $295,000, and $354,000 for larger floor plans. The three sizes Azusa already pre-approves (800 sq ft and 1,000 sq ft) line up with the lower end of that range. Costs beyond the prefab model depend on lot conditions (slope, utilities run length, fire-zone construction, plan changes) and on whether the unit is detached, attached, or a conversion. CSLB license number is 1095476. For a custom detached ADU the cost is driven by the floor area, finish level, the number of corners that need utility trenching, and any required fire-sprinkler retrofit, so the published model prices are a starting reference for the design-build scope rather than a fixed total.

What impact fees will I pay on an Azusa ADU?

Under California Government Code Section 66311.5(c)(1), an ADU of 750 sq ft or smaller is exempt from school and most local impact fees, regardless of where it is built. Above 750 sq ft, impact fees are still capped at a proportional share of the impact fees that would apply to the primary dwelling on the same lot. Azusa follows the state framework, so a detached 800 sq ft ADU or 1,000 sq ft ADU pays impact fees only on the area above 750 sq ft, applied proportionally. The same proportional rule applies to a JADU at 500 sq ft, which falls below the 750 sq ft threshold and is exempt from impact fees under the same section. Plan check fees, building permit fees, and any utility connection fees from Azusa Light and Water are billed separately from impact fees.

What should I check before building an ADU in Azusa?

Verify four items before submittal. First, a recent title report or property survey showing the legal lot description and dimensions, because the City's Building Division handout asks for them on the cover sheet. Second, a High Fire Hazard Severity Zone map check, since Chapter 7A wildfire construction standards apply to mapped portions of Azusa. Third, the registered CF1R energy calculations from cheers.org or calcerts.com, since the Building Division submittal handout requires them. Fourth, the architect or engineer of record must stamp every sheet and list the current edition of the California Residential Code, Electrical Code, Plumbing Code, Mechanical Code, and Los Angeles County Fire Code. Garages that are converted need a stem-wall detail at the original garage door opening. City Hall is at 213 E Foothill Boulevard, Azusa, CA 91702, and the Planning Division opens weekdays for in-person questions on applications and the pre-approved plan set.

Official Azusa ADU sources

• The Azusa Planning Division Accessory Dwelling Units (ADU) and (JADU) page lists three pre-approved ADU plans under Ordinance 2024-08: an 800 sq ft 2 bed/2 bath and two 1,000 sq ft 3 bed/2 bath designs, all submitted to the city by Aligcus Construction, with a JADU defined as a separate unit no larger than 500 sq ft that must be owner occupied. Official source
• The Azusa Building Division ADU Submittal Requirements handout caps a detached ADU at 1,200 sq ft, an attached ADU at 50% of the existing dwelling area (excluding garage) and 1,200 sq ft, height at 16 ft, with 10 ft of horizontal separation from the main house and a 36 inch wide passageway required from the street to the main dwelling entry. The same handout allows an accessory structure conversion to expand by 150 sq ft beyond the same physical dimensions as the existing structure. Official source
• California Government Code Section 66317(a)(2) requires a written completeness determination within 15 business days from submittal, and Section 66317(a)(3) gives the permitting agency 60 days from receipt of a complete application to approve or deny, with the application deemed approved if the 60 day clock runs out without an applicant-requested delay. Official source
• California Government Code Section 66314(d)(5) caps a detached ADU at 1,200 sq ft of floor area, and Section 66314(d)(7) caps side and rear yard setbacks for an ADU at 4 ft. The same section treats one detached ADU as the base allowance on a single-family lot. Official source
• California Government Code Section 66311.5(c)(1) prohibits a local agency, special district, or water corporation from imposing any impact fee on an ADU that has 750 sq ft of interior livable space or less, and requires impact fees on a larger ADU to be charged proportionally in relation to the primary dwelling square footage. Official source
• California Government Code Section 66321(b)(2) sets statewide minimum floors that a local ordinance cannot undercut at 850 sq ft for a studio or one bedroom detached ADU and 1,000 sq ft for a multi-bedroom detached ADU. Section 66321(b)(3) creates an 800 sq ft ministerial ADU envelope with a four foot side and rear setback. Official source
• California Government Code Section 66313 defines an ADU and a JADU, with Section 66313(d) capping a JADU at 500 sq ft of interior space and requiring it to be contained entirely within an existing or proposed single-family residence, with separate conveyance prohibited under Section 66333. Official source