Live Full-Time in a Tiny Home on Wheels in Unincorporated San Diego County (2026)
Big news for tiny home fans: in unincorporated San Diego County, a tiny home on wheels can now be your main home. You don't need a big house on the lot first. Here's what the County's rule says, in plain words.
Ready to start? Fill out the Zen Tiny Homes Buyers Application or call Zen Tiny Homes at 760-492-0742.
What Changed
On September 4, 2025, the County's Planning & Development Services director issued a Director's Determination. It says a tiny home on wheels (THOW) built to the ANSI A119.5 park model standard counts as a "dwelling" under the County's zoning rules, so it "could be used as a primary or an accessory dwelling."
A few key points:
It covers unincorporated San Diego County, not cities.
It does not change how many homes your lot is allowed. Zoning and density rules still apply.
A THOW that meets the rules can go on any lot that allows a single-family home, once a building permit is issued.
Used as your main home, it must meet the same setbacks and zoning rules as a main house.
It must sit on private land, not in a County road right-of-way.
The Main Requirements, in Plain Words
From the County's Tiny Homes on Wheels page and the Director's Determination:
Certification: designed and built to the ANSI A119.5 park model standard, with a third-party certification sticker before the permit is issued. All Zen Tiny Homes are built to ANSI standards.
Size: up to 430 square feet (inside the walls), one story, plus a sleeping loft up to 150 square feet. No taller than 16 feet.
No slide-outs or pop-outs, and it can't move under its own power.
Stays registered with the California DMV.
Fire safety: noncombustible or ignition-resistant outside walls, a Class A roof, dual-glazed windows with a tempered pane, smoke and carbon monoxide alarms, and a way out of any loft.
Fire sprinklers: required, unless the home is used as an ADU and ADU exemptions apply.
Insulation: at least R-13 in exterior walls.
Parking pad: a paved pad (2 inches of asphalt or 3 inches of concrete) with curbs or bumper guards so it can't roll.
Spacing: at least 6 feet from other buildings.
Utilities: connected to electric, water and sewer, with the required building permits.
Equipment: heating and cooling equipment built into the home, not on the roof.
Why It Matters
You can own land and live on it in a tiny home without building a full-size house first.
A tiny home on wheels is built off-site, so less building happens on your land.
If you ever remove it, the County requires a demolition permit to take it off the records.
How Zen Tiny Homes Helps
$500 site assessment: we check your lot, delivery access and utility hookups, and what fits your lot.
Plans: the Alpine (a flex plan in 20', 22' or 24', from $50K), the Mammoth (up to 30', from $75K), the Container (from about $40K), or Custom.
Build and delivery: built off-site, then delivered and set up on your pad.
Reserve your spot: a $500 deposit holds your place on the build list.
Still shopping for land? Read Buying Land for a Tiny Home in Unincorporated San Diego County. New to all this? Start with 7 Steps to the Tiny Home Dream. Adding one behind your house instead? See Backyard Tiny Homes in San Diego.
Related Guides
Frequently Asked Questions
Can a tiny home on wheels be my only home in San Diego County?
Yes, in unincorporated areas. Since September 4, 2025, the County treats a qualifying tiny home on wheels as a dwelling that can be a primary or accessory home, as long as it meets the County's requirements.
Does this apply inside cities like San Diego or Escondido?
No. This County rule covers unincorporated areas only. Cities set their own rules. Rules vary by property; Zen's $500 site assessment checks what fits your lot.
How big can it be?
Up to 430 square feet, measured inside the walls, with one story plus a sleeping loft up to 150 square feet, and no more than 16 feet tall.
Do I need fire sprinklers?
Yes, for a tiny home on wheels used as a main home. The County lets ADU exemptions apply only when the home is used as an ADU.
Floor Plan Preview
Here's a look at two of the designs Zen Tiny Homes can build. Every plan can be adjusted to fit your lot.
Jamul Bungalow: 3D exterior
Jamul Bungalow: floor plan
See all the layouts in California Tiny Home Floor Plans.
Ready to Live Tiny Full-Time?
The best first step is a site assessment of your lot. Tell us about your plans and we'll help you pick the right home.
Prefer to talk? Call Zen Tiny Homes at 760-492-0742 or visit zentinyhomes.com.
This guide is general information, not legal advice. Rules change and vary by property. Zen's $500 site assessment checks what fits your lot, or call 760-492-0742.
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