Coronado Zoning and ADU Guide for Homeowners

Last updated November 13, 2026. Reviewed by the Cash Home Buyers CA team.

Coronado’s Planning and Zoning Division implements the General Plan, the Local Coastal Program and the zoning ordinance, and ADU rules sit in Coronado Municipal Code section 86.56.105. This guide explains what the city says about ADUs and junior ADUs, how parking and floor area apply, and what to do if you own a home with a converted garage or an older unpermitted unit.

Coronado zoning and ADUs at a glance

Division	Planning and Zoning Division, Community Development Department
Responsible for	General Plan, Local Coastal Program and zoning ordinances
ADU ordinance	Coronado Municipal Code section 86.56.105, updated to follow state ADU law at the time of adoption
Junior ADU	Up to 500 square feet and contained within the single-family home
Parking	Deed-restricted ADUs (low, very low or extremely low income) are exempt; one space for carriage house conversions unless deed-restricted
Floor area	The city’s 2021 council actions say the residence and an ADU must comply with floor area ratio and other development standards
Phone	(619) 522-7326 (Community Development)

What Planning and Zoning answers

The city says Planning and Zoning responds to general inquiries about a property’s zoning and development regulations such as setbacks and allowable building heights. Coronado is an island city with a Local Coastal Program, so some projects need more than a building permit. Ask Planning which zone your lot is in and whether any overlay applies before you pay for drawings.

ADUs and JADUs in Coronado

The city’s ADU page explains that junior accessory dwelling units are similar to ADUs but are limited to 500 square feet and must be contained within the single-family residence. Section 86.56.105 of the Municipal Code governs ADUs and, according to the city’s Housing Element fact sheet, was updated throughout to comply with state law at the time of adoption.

On parking, the same fact sheet says ADUs deed-restricted to low, very low or extremely low income levels are exempt from parking requirements, and that one parking space is required for a carriage house conversion unless the unit is deed-restricted to low-income levels.

Council actions in early 2021 also say a residence and an ADU must comply with floor area ratio and other applicable development standards, which can limit how big a unit can be on a given lot.

The city’s draft Housing Element estimated 190 ADUs over the 6th planning cycle, so the city expects them to be a real part of its housing supply.

How to start in Coronado

1. Confirm your zone and lot

Ask Planning to confirm your zoning, floor area ratio and any coastal requirements.

2. Read the current ordinance and handout

The city’s ADU page and section 86.56.105 carry the current standards. Because the ordinance changes with state law, treat the city’s current text as final on size, height and parking.

3. Design to the standards

Confirm setbacks and height in writing before you pay for drawings.

4. Plan check and permits

Submit plans to Building Services. See our Coronado permits guide for plan review timing and submittal requirements.

State ADU law and Coronado

California’s ADU statute, Government Code section 66314 and following, sets a floor that every city must follow, and local ordinances fill in the details.

The state requires ministerial review within 60 days of a complete application, bars a city from requiring more than a limited set of standards, and generally allows an ADU or conversion inside existing space without added setbacks.

The California Department of Housing and Community Development (HCD) publishes a handbook and keeps a list of the state requirements. Because state law changes often, treat the city’s current ordinance and handout as the final word on size, height, parking and fees for your lot.

ADUs, garage conversions and selling a Coronado house

Many older homes have a converted garage or a backyard unit built without permits. Buyers and lenders ask about them, and California sellers generally disclose known unpermitted work. Our guide to selling as-is with unpermitted work explains the rules, and our Prop 13 guide explains how new construction can affect property tax. Before you list:

• Check city records for permits on any ADU, conversion or addition.
• Ask Planning whether the structure could qualify under current rules.
• Estimate plans, fees and corrections needed to legalize it.
• Compare that with selling as-is and letting a cash buyer take on the legalization.

Questions to ask Planning before you design

• Does my lot and zone allow an ADU, a junior ADU, or both?
• Is a pre-approved or pre-reviewed ADU plan available?
• What are the current impact, utility and school fees for the size I am considering?
• Can my existing garage or accessory structure be converted without changing its footprint?
• Are there fire, slope, easement or utility constraints on my lot?

Junior ADUs and garage conversions in more detail

State law treats a junior ADU as a unit of up to 500 square feet created inside the walls of an existing or proposed single-family home, with an efficiency kitchen and a recorded restriction that keeps it from being sold apart from the house.

A garage conversion is a different path: the unit replaces the garage, and state law generally does not require the city to demand replacement parking. Both are common sources of unpermitted space in older Coronado neighborhoods, which is why buyers’ agents and appraisers ask for the permit record.

If a conversion was done without a permit, the usual fix is to submit as-built drawings, pay the fees and pass inspection, which can take months and cost real money.

Fees, utilities and property tax

State law limits the impact fees a city can charge on smaller ADUs and on conversions of existing space, and it limits when a separate utility connection can be required.

Larger new units can still carry impact fees, school fees and water or sewer connection charges, so ask for an itemized estimate before you commit to plans. New construction is generally reassessed for property tax under Prop 13, which means an ADU can raise the bill for the whole property. Our Prop 13 guide explains how reassessment works.

Why ADUs matter for resale

A permitted ADU can add rental income and appeal for some buyers, but an unpermitted one can complicate financing and appraisal. Lenders typically want permitted living area, and an appraiser may not count unpermitted space.

Because an ADU generally cannot be sold separately from the main home, its value comes through the sale of the whole property.

If you inherited a house with an old backyard unit, or bought one with a converted garage, check what the city has on file before you decide how to sell. Our probate home sale guide covers inherited property.

How to sell a house in Coronado

1. Check which structures on the property are permitted ADUs, conversions or unpermitted.
2. Collect permits, plans and any city notices.
3. Request a no-obligation cash offer for the house as it stands.
4. Choose your closing date.
5. Close with no legalization, repairs or showings required.

See also our Coronado page and the San Diego County hub.

Frequently asked questions

Does Coronado allow ADUs?

Yes. The city has an ADU and JADU page and regulates them in Municipal Code section 86.56.105.

How big can a junior ADU be in Coronado?

The city says JADUs are limited to 500 square feet and must be contained within the single-family residence.

Does a Coronado ADU need parking?

Deed-restricted low-income ADUs are exempt, and a carriage house conversion needs one space unless it is deed-restricted, according to the city’s fact sheet.

Does floor area ratio apply to ADUs?

City Council actions in 2021 say the residence and an ADU must comply with floor area ratio and other development standards.

Who answers zoning questions in Coronado?

The Planning and Zoning Division of Community Development, which handles setbacks, heights and zoning inquiries.

Can I sell my Coronado house with an unpermitted ADU or garage conversion?

Yes. You can disclose it and sell as-is, including to a cash buyer. Our statewide guide explains the disclosure rules.

More guides

• We Buy Houses in Coronado
• We Buy Houses in San Diego County
• San Diego County Property Tax Guide
• Coronado Building Permits Guide
• Coronado Code Enforcement Guide
• All California Guides

Sources

• City of Coronado: ADUs and JADUs
• City of Coronado: Planning and Zoning
• City of Coronado: Housing Element Ordinance Amendments Fact Sheet
• California HCD: Accessory Dwelling Units

This guide is general information from public sources, not legal advice. Confirm current rules, fees and hours with the city.