ADU Builder in Alhambra, CA: Permits, Costs and Local Rules

What size and height does an Alhambra ADU get on a single family lot?

The Alhambra Accessory Dwelling Units page states that on a lot with no more than one existing or proposed single family dwelling, a detached ADU is allowed a maximum of two stories, a maximum height limit of 25 feet, a minimum building separation of 5 feet eave to eave, and a floor area not to exceed 1,200 square feet. An attached ADU on the same lot is allowed a maximum of two stories, a maximum height limit of 25 feet, and a floor area not to exceed 50% of the existing main dwelling unit floor area, or 850 square feet for an ADU with 1 bedroom or less, and 1,000 square feet for an ADU that provides more than 1 bedroom, whichever is greater. The Alhambra ADU Informational Handout repeats the same standards in table form and adds the state 800 square foot exemption with 4 foot setbacks.

How many ADUs and JADUs can an Alhambra lot have?

The Alhambra Accessory Dwelling Units page states that on a lot with a single family dwelling, the number of ADUs permitted is one detached or attached ADU, plus one conversion ADU created from space within a proposed or existing single family dwelling or accessory structure, plus one JADU, with owner occupancy required for JADUs that share sanitation facilities with the primary unit. The page also states that on a lot with a multi family dwelling, the number of ADUs permitted is two detached ADUs on a lot with a proposed multi family dwelling, or up to eight detached ADUs on a lot with an existing multi unit dwelling not to exceed the number of existing units on the lot, plus conversion ADUs created within the portions of existing multifamily structures that are not used as livable space up to 25% of the number of existing units. JADUs are not allowed on properties with existing or proposed multi family structures.

What setbacks and parking apply to an Alhambra ADU?

The Alhambra Accessory Dwelling Units page states there shall be at least a four foot side and rear yard setback for a new attached or detached ADU, that exterior mechanical equipment shall have at least a three foot setback from any property line, and that no setback shall be required for ADUs created within an existing living area, within an existing accessory structure, or in a new structure created in the same location and within the same dimensions as an existing structure, however the existing setbacks must be sufficient for fire and safety. The page states that all new ADUs will be required to provide one additional parking space, covered or uncovered, if the proposed ADU is not within a one-half mile radius of a public transit station, and that for accessory structures or a portion of the existing residence that is converted into an ADU, no additional parking is required. Parking is not required for JADUs.

How is an Alhambra ADU permit reviewed?

The Alhambra Accessory Dwelling Units page states that an ADU requires a Building Permit which applicants will obtain by submitting for Plan Check with the Building Division, that ADU Permit Applications must be submitted to the Building Division through the online Permit Portal, that the Building Division will then route plans to each of the applicable Departments and Divisions for review, and that upon receiving departmental approvals, the applicant will then be issued a Building Permit. The Alhambra ADU Informational Handout lays out the review steps in order: Permit Tech Application Review, Planning Initial Review, Corrections and Resubmittal, Pay Plan Check Fees, Ready for Plan Check with concurrent Building, Fire, and Public Works review in GoPost, Utilities review for water service and sewer connections, Outside Agency Referrals including LA County Sanitation, AUSD if the ADU is greater than 500 square feet, and AQMD if demolition is included in the scope, C and D Waste Diversion Forms, Permit Holder Declaration, Pay Permit Fees, Permits Issued, Pass Required Inspections, and Permits Finaled.

How much does an ADU cost in Alhambra?

L Square publishes configured model prices on the cost guide page: $180,000 for Model 600, $240,000 for Models 800A and 800B, $295,000 for Models 1000A and 1000B, and $354,000 for Model 1200. These are model prices, not a final total for your lot. Alhambra lots also carry the published Building Permit and Plan Check fees from the Informational Handout, the Fire Department ADU Plan Check fee, separate school fees where the project exceeds the school district threshold, separate mechanical, electrical, and plumbing sub permits, and utility and connection fees from the providers listed on the city pages. Garage conversions, attached ADUs, and JADUs are priced from a property specific scope because each one depends on the existing structure and the lot layout.

What should you confirm before building in Alhambra?

Check three things before drawings are final. First, confirm that your project qualifies for an ADU under state law: a local agency cannot set a maximum ADU size below 850 square feet for a studio or one bedroom and 1,000 square feet for more than one bedroom, and an 800 square foot pathway is protected under specified height, setback, and other standards, per Gov. Code 66321. Second, confirm whether the JADU owner occupancy requirement applies to your JADU; the city applies it to JADUs that share sanitation facilities with the primary unit under the local ADU standards, and a JADU is limited to 500 square feet of interior livable space under Gov. Code 66333. Third, confirm which Alhambra handouts apply to your submittal, including the Informational Handout, the Zoning Code, and the ADU Permit Application materials linked on the Accessory Dwelling Units page. Building Division intake happens through the online Permit Portal.

Official Alhambra ADU sources

• The Alhambra Accessory Dwelling Units page states that on a lot with no more than one existing or proposed single family dwelling, a detached ADU is allowed a maximum of two stories, a maximum height limit of 25 feet, and a floor area not to exceed 1,200 square feet; an attached ADU is allowed up to 50% of the existing main dwelling unit floor area, or 850 square feet for 1 bedroom or less, and 1,000 square feet for more than 1 bedroom, whichever is greater. Official source
• The Alhambra Accessory Dwelling Units page states that on a lot with a single family dwelling the number of ADUs permitted is one detached or attached ADU, plus one conversion ADU, plus one JADU, and that JADUs are not allowed on properties with existing or proposed multi family structures. Official source
• The Alhambra Accessory Dwelling Units page states there shall be at least a four foot side and rear yard setback for a new attached or detached ADU, that all new ADUs are required to provide one additional parking space if the proposed ADU is not within a one-half mile radius of a public transit station, and that parking is not required for JADUs. Official source
• The Alhambra Accessory Dwelling Units page states that an ADU requires a Building Permit which applicants will obtain by submitting for Plan Check with the Building Division, that ADU Permit Applications must be submitted to the Building Division through the online Permit Portal, and that City Hall is at 111 South First Street, Alhambra, CA 91801, with hours Monday through Thursday 7 a.m. to 5:30 p.m. Official source
• The Alhambra Accessory Dwelling Units page states that on a lot with a multi family dwelling the number of ADUs permitted is two detached ADUs on a lot with a proposed multi family dwelling, or up to eight detached ADUs on a lot with an existing multi unit dwelling not to exceed the number of existing units, plus conversion ADUs up to 25% of the number of existing units. Official source