License: No. #1076712
Discover what you can build in the City of Altadena. This city guide covers essential Custom Home regulations and zoning laws to help you navigate the process and make informed decisions for your property.
In Altadena you can build one attached Custom Home, one detached Custom Home, and one JCustom Home on single-family property.
Multifamily property owners in Altadena may convert at least one Custom Home, and additional Homes not to exceed a maximum number equal to 25% of the existing units out of existing uninhabitable space. Ergo:
No more than two detached Homes may be constructed on a multifamily lot in Altadena.
In Altadena, the maximum size for a detached Custom Home is 1,200 square feet.
In Altadena an attached Custom Home can be up to 1,200 square feet or 50% of the size of the main dwelling unit, whichever is smaller.
In Altadena, detached Homes are limited in height to 25 feet. An attached Custom Home can be up to 25 feet or the height of the main dwelling unit, whichever is smaller.
Yes, you can build a two-story attached or detached Custom Home in Altadena.
No, stacked Homes (one Custom Home on each floor of a two-story structure) are not allowed in Altadena.
No, two Homes attached together are not allowed in Altadena.
No, a JCustom Home is defined as A Custom Home converted from existing space within the main structure of the primary dwelling unit. As such, it cannot be attached to A Custom Home.
Roof decks are not prohibited for Homes in Altadena. However, California building safety codes about roof deck safety railings apply, and the height of the railing applies to the total height of the building, so the whole structure including the railings must comply with Custom Home height requirements. California requires that deck rails be 36 inches high on residential dwellings, 42 inches high on multifamily dwellings.
The exterior of the Custom Home must align with the architectural and aesthetic style of the rest of the neighborhood, using similar materials and design elements to maintain consistency with the main dwelling unit and surrounding dwellings.
The City of Altadena requires 4-foot rear and side setbacks for new-construction Homes. Homes converted from existing structures may be exempt.
The City of Altadena requires a minimum of 6 feet of separation between the new Custom Home and any other structures. Homes converted from existing structures may be exempt.
No, Homes are not allowed in the front yard of residential property in Altadena.
No, you can also submit plans online to the LA County Department of Regional Planning using the EPIC-LA online submission system.
Altadena may require a soils report for Custom Home permitting to make sure the soil can support the new structure, especially if the Custom Home will be located on a hillside, an area with significant grading, or if there are special foundation requirements.
While not setting a percentage, Altadena requires that property maintain “sufficient” open and permeable space on the lot.
The plan check requires a review by the Department of Regional Planning and the Department of Building & Safety for zoning, building standards, and safety compliance. The process takes approximately 4-6 weeks.
Altadena typically requires one additional parking spot per Custom Home be added to the property. However, if the property is located within a half-mile of a public transit stop, it may be exempt from this requirement. Homes converted from an existing garage or carport are also exempt from this parking requirement.
If a parking space must be added, it can be included on the driveway or configured as tandem parking.
Per Title 24 of the California Energy Code, solar panels of appropriate size and capacity are mandatory on new-construction Homes. Homes built from converted existing structures are exempt, as may be Homes located under significant shading. Smaller Homes may be subject to reduced or modified solar panel requirements.
A Custom Home is not required to have a separate water or electrical meter. You can opt for the Custom Home to share service with the main dwelling unit. However, you can request separate water or electrical meters from the City of Altadena.
Altadena does not automatically assign a new Custom Home its own address. However, it may assign the Custom Home a new address if it is intended for rental or independent occupancy. The Custom Home will usually get a “½” designation — for example, A Custom Home located behind 1234 Pine Street would have the address “1234½ Pine Street.”
Low Impact Development (LID) is an approach to land development or redevelopment that seeks to preserve and conserve onsite water quality and natural features, with minimal detrimental effect to local waterways and ecosystems. Altadena may require LID fees for larger Homes.
No, Altadena does not allow residents to use A Custom Home as an Airbnb or short-term rental (30 days or less).
Per the Costa-Hawkins Act of 1995, Altadena does not impose rent control on dwellings constructed after February 1, 1995. This means most new-build Homes are exempt. However, if the primary dwelling unit is subject to rent control, it might apply to the Custom Home as well.
While encouraging the use of electric appliances for efficiency and sustainability, Altadena does not prohibit gas appliances in new Homes.
In Altadena you are only required to install sprinklers in a new Custom Home if the primary dwelling unit has them as well. You may also be required to install them if the Custom Home is located within a special fire hazard zone.
