Detached ADU
A separate backyard home with its own entrance.
City guide · Riverside County
ADUs in Moreno Valley, California
Moreno Valley offers two ways to submit an ADU: city pre-approved plans or custom-designed plans. The city defines an ADU as an attached or detached unit with complete, independent living facilities. Here is what Moreno Valley homeowners should know.
What is an ADU?
An Accessory Dwelling Unit is a smaller, independent home on the same lot as a primary residence. California law sets a statewide baseline for ADUs, and each city administers its own planning review, permits and inspections.
Types of ADUs to consider
Attached ADU
Built onto the existing home with independent exterior access.
Garage or space conversion
Turns existing space, such as a garage, into a living unit.
Junior ADU (JADU)
A smaller unit created within the walls of the existing home.
What the city says
- The city owns seven pre-approved detached ADU plans, from a 306 sq ft studio to a 988 sq ft three-bedroom.
- To use pre-approved plans, the lot must be zoned residential with an existing single-family home or duplex, and must not be in a geo-hazard, landslide, flood or Wildland-Urban Interface (WUI) area.
- Custom ADU types listed by the city include detached, attached, converted-space and junior ADUs. Travel trailers, tiny homes on wheels and uninsulated sheds are not ADUs.
- Plan review, permits and inspections run through SimpliCITY, the city's online portal.
Facts on this page come from the official sources listed. Requirements can change — confirm with the city before you design or build.
How the ADU process usually works
- Learn what your city allows and check your property's zoning and site conditions.
- Set a budget and choose a pre-approved plan or a custom design.
- Prepare plans and submit them to the city for planning and building review.
- Respond to plan-check comments, pay fees and receive your permit.
- Build with required city inspections, then receive final approval.
Official resources
- City of Moreno Valley — Accessory Dwelling Units
- City of Moreno Valley — Pre-Approved ADU Plans
- City of Moreno Valley — Building and Safety Division (SimpliCITY)
Moreno Valley permit counter: permitcounter@moval.org or 951-413-3350, option 5.
Statewide guidance
Common questions
Can I use a pre-approved plan for an attached ADU?
The city's pre-approved plans are for free-standing (detached) ADUs. Attached, converted-space and junior ADUs follow the custom-design path with their own checklists.
How big can my ADU be, and what setbacks apply?
Size limits, setbacks, height and parking rules depend on your lot, zone and ADU type. ADU California does not publish these numbers unless we can source them directly. Confirm them with the City of Moreno Valley Community Development Department before you design.
How much are permit fees and how long does approval take?
Fees and review times change and vary by project. Ask the City of Moreno Valley Community Development Department for current fees and timelines. Our cost estimator gives a planning-level range, not a quote.
How ADU California can help
Use our free tools to understand your property and plan your budget. We are an independent homeowner resource, not a government agency — always confirm requirements with the city.
Information reviewed: 2026-10-08 · Other locations