Garden Grove, CA Accessory Structures: Tiny Homes (2026)

Garden Grove Municipal Code Chapter 9.54 (Accessory Dwelling Units and Junior Accessory Dwelling Units), updated by Ordinance Nos. 2882, 2929, and 2966, is the primary pathway to permit a tiny home as a permanent residence. Section 9.54.040 caps detached ADU floor area at 850 sq ft for a studio or one-bedroom and 1,200 sq ft for two or more bedrooms; minimum sizes are 150 sq ft (efficiency), 220 sq ft (studio), 500 sq ft (one-bedroom), and 700 sq ft (two-or-more bedrooms). Detached ADUs are limited to 16 feet in height for a single-story structure, with state-allowed exceptions in Cal. Gov. Code 65852.2 for transit-adjacent and above-garage units. Attached ADUs may follow the primary structure height up to about 25 feet. Side and rear setbacks are a minimum of 4 feet, and replacement parking is not required when an existing garage is converted to an ADU. A Junior ADU is capped at 500 sq ft, must be inside the walls of an existing or proposed single-family home, requires a recorded deed restriction, and triggers an owner-occupancy requirement on the property. The City accepts manufactured homes built to California Health & Safety Code 18007 standards on a permanent foundation as ADUs; tiny houses on wheels (THOWs) and park-model recreational vehicles fall under Cal. H&S Code 18028 as RVs and cannot be used as permanent dwellings outside a permitted RV or mobilehome park. SB 9 two-unit and lot-split projects are governed separately by GGMC Chapter 9.55. Building, electrical, plumbing permits, and connection to City water and sewer are required before occupancy.