Planning an ADU in Los Angeles County? Here are some Resources.
Two agencies must approve your plans; Regional Planning determines if your plans conform to zoning requirements – height, setback, etc. The Department of Building & Safety will make sure that your little unit conforms to all building codes for a dwelling.
Accessory Dwelling Unit Handbook
Start with this online booklet by the California Department of Housing and Human Development.Well written overview of ADU issues.
Step-by-Step Guide for Accessory Dwelling Units in Los Angeles Unincorporated Areas
Covers the steps required by County zoning and permitting.
Ordinance 2020-0059 – Title 22
Amendment to Los Angeles County code establishing development standards for ADUs.
Public Works Los Angeles
County Building & Safety
Homeowner’s Guide. How to Successfully Plan and Prepare for your next Accessory Dwelling Unit (ADU)/ Junior Accessory Dwelling Unit (JADU) Project
Covers all steps and requirements for building permits and construction once zoning has been approved.
LA County Planning
Planning Permits for Accessory Dwelling Units
Basic ADU information with links to other pages. Links to a Standard ADU Plans Program with pre-approved construction plans that streamline Building and Safety approval.“Coming soon” they tell us.
LADPW Accessory Dwelling Unit –Expedited Plancheck Submittal Checklist
Building & Safety checklist of most everything that needs to be specified or shown on plans for ADUs
California Housing Finance Agency (CalHFA) Grant Program
ADU Grants up to $40,000 towards pre-development and non-reoccurring closing costs. Predevelopment costs include site prep, architectural designs, permits, soil tests, impact fees, property survey, and energy reports.
Neighborhood Housing Services of Los Angeles County (NHS)Assists low income households access favorable financing.
Altadena Housing by the Numbers
Altadena Population in 2023 – 43,384
Area in square miles – 8.5
Population Density – 5,124.5 per square mile
(Compared to LA’s 8038 per square mile)
Total housing units – 15,860
Percentage of homes that are owned – 74%
Percentage that are rentals– 26%
Granny flats approved from 2017 to 2022 – 458
Median home price – $879,600
Median rent – $1834 /month
Median mortgage – $3130 / month
Median real estate taxes – $5343/ year
Source: Town charts
Altadena-CDP-CA-Housing-data.html