What are the tiny house laws in California?

California allows tiny homes with an approved construction classification at an approved site¹. Calling a structure a ‘tiny home’ does not give you permission to live there¹. HCD lists manufactured homes, code-built homes, factory-built housing, RVs, park trailers and camping cabins as possible classifications¹. Each classification has different construction and occupancy conditions¹.

To live legally in a structure outside those classifications, you must meet California's building standards¹. Before you buy, ask the local building department which approval route fits your proposed home. Bring the manufacturer's plans and describe your intended site. Ask specifically about approval to live there permanently.

California gives you no blanket right to live permanently in a tiny home on wheels on private land¹. California says RVs are not intended as permanent dwellings¹. RV occupancy generally belongs in mobilehome parks or special occupancy parks unless a local ordinance allows otherwise¹.

Some counties allow movable tiny homes, including primary or accessory homes, under local conditions⁵. Wheels alone do not determine whether your home can be approved¹. Ask the planning office which ordinance allows your specific use. Explain whether you want a primary residence, an accessory home or temporary housing. Before you pay a deposit, ask for the installation and occupancy conditions in writing.

California's 150-square-foot efficiency-unit option does not set a universal minimum for every house³. Health and Safety Code section 17958.1 lets local governments allow these units by ordinance³. No more than 2 people can live in one³. The ordinance can allow partial kitchen or bathroom facilities, but other applicable minimum standards still apply³.

California's current building standards apply to applications dated January 1, 2026 onward². You also need to account for local zoning and setback requirements⁶. Ask the building department for the minimum floor area and room standards for your exact classification. Ask for a separate answer for a foundation dwelling, an efficiency unit or a manufactured home.

Your tiny house can use California's state ADU approval route if it qualifies as an accessory dwelling unit⁷. State law calls for approval without discretionary review or a hearing⁷. Within 15 business days of receiving your application, the local agency must tell you in writing whether it is complete⁷. If your application is incomplete, the agency must list missing items and explain how to complete it⁷.

Calling your tiny home an ADU does not settle its construction classification or site approval¹. Your ADU project still needs to meet local building, health, fire and utility requirements⁷. Ask the planning office whether your proposed unit qualifies for state ADU approval. For a movable unit, ask which local ordinance allows that arrangement.

In California, your tiny home needs approval for both its site and construction classification¹. Ask the planning office whether your parcel allows the proposed dwelling use. Then ask the building department which plans, inspections and occupancy approvals you need. Ask for an itemized estimate of building, installation and utility charges.

New and replacement septic systems need approval from the applicable local or regional authority⁴. Local septic standards can be more protective than California's statewide minimums⁴. Ask the local environmental health office whether your site can support the wastewater system you propose. For questions about HCD's tiny-home guidance, call its Division of Codes and Standards⁸. Ask for current guidance for your home's classification before you commit to the purchase.