San José runs one of California's most homeowner-friendly ADU programs, with a dedicated ADU Resource Center, an ADU Ally support channel, multilingual guides, and a Pre-Approved ADU Plan Program with vendor partners.
Allows ADUs across eligible residential zoning. Includes Junior ADUs under 500 sq ft and city materials cover Tiny Homes on Wheels (THOWs) where applicable.
State guarantee: California requires every city to allow at least an 800 sq ft ADU exempt from local lot coverage, FAR, and front-setback rules.
Height baseline: 16 ft for detached, rising to 18 ft within ½ mile of major transit. Attached ADUs follow the primary home, capped at 25 ft.
California state ADU parking limitations apply. City checklist flags location constraints (hazards, WUI, flood) that can affect what is buildable even when parking is not the main issue.
Centralized under Development Services / Permit Center. ADU Resource Center hub with Universal Checklist, FAQs, and process pages. ADU Ally staff contact (email/phone). Pre-approved plan track for faster review.
State backstop: A complete ADU permit must receive a decision in 60 business days. If the city stalls past 30 business days, AB 253 lets you hire a certified private plan checker to force a 10-business-day decision.
City provides an online permit cost estimator. Fee deferrals/waivers depend on current Council programs.
SB 543: No impact fees on ADUs ≤750 sq ft. Above 750 sq ft, fees scale to the ratio of ADU size vs the main home.
Visit the official San José ADU page (link in hero) for current eligibility and downloads.
Standard ADUs in San José: no owner-occupancy required (made permanent in 2023).
JADUs: limited to 500 sq ft of interior livable space within an existing single-family home. Owner occupancy is required only when sanitation facilities are shared with the main house. JADUs cannot be used as short-term rentals (AB 1154 / SB 543).
Sketch a floorplan, walk through it in 3D, and have our planners review it for size, height, and setback compliance before you submit to San José.
Heads up: Local rules change frequently. This page summarizes publicly available state law (California Government Code §§ 66310–66342) and current local guidance for general planning purposes. Always confirm specifics with the San José planning desk before submitting plans. ADUMetrics does not provide legal advice.