Santa Maria Zoning and ADU Guide for Homeowners

California Cash Home Buyers

Cash Offer in 24 Hours

No repairs or cleanup
No fees or commissions
Close on your timeline

Selling a Santa Maria home with an ADU or garage conversion?

Get a straight cash offer, as-is, with no permit cleanup required.

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

Santa Maria regulates accessory dwelling units (ADUs) and junior ADUs under Chapter 12-56 of its municipal code, last amended effective December 4, 2025, which requires a building permit, approves compliant applications ministerially within 60 days, and sets size, height, setback, parking and owner-occupancy standards that follow California Government Code sections 66314 and 66333 and following. This guide summarizes the city’s published code and what it means if you own, build or plan to sell a home with an accessory unit.

Santa Maria ADU rules at a glance

Approval	Ministerial building permit, no discretionary review or hearing; approve or deny within 60 days of a complete application, or it is deemed approved unless a delay was requested
Where allowed	Residential or mixed-use zones with an existing or proposed home; JADUs only on single-family lots (R-1 and RSL-1)
Detached ADU, state-protected tier	Up to 800 square feet, four-foot side and rear setbacks
Other ADUs (one attached or detached)	850 square feet for a studio or one bedroom, 1,000 for two or more bedrooms; attached units also limited to 50 percent of the main home
JADU	No more than 500 square feet, within the home or attached garage
Height, detached single-family lot	18 feet, up to 20 with a matching roof pitch; 16 feet if the lot also has a JADU
Parking	One space per ADU or per bedroom, whichever is less, with several exceptions
Rental and sale	Rent for 30 days or longer; no separate sale except as state law allows

Two ways an ADU can be approved

The code approves ADUs in two groups. The first follows Government Code section 66323 and is approved by the Community Development Director with a building permit.

It covers a converted unit or JADU inside a single-family home, attached garage or existing accessory structure, with an addition of up to 150 square feet only for ingress and egress; a limited detached new-construction ADU of up to 800 square feet with four-foot side and rear setbacks; converted non-livable space on multifamily lots, up to 25 percent of the units and at least one; and, on lots with an existing multifamily building, up to eight detached ADUs but no more than the number of existing units.

The second group covers other ADUs: one attached or one detached ADU is allowed for each lot with a single-family home or a proposed home on a vacant lot, and no ADU may be built or legalized without a building permit that meets the code’s development standards.

Size, lot coverage and height

For ADUs in the second group, the maximum is 850 square feet for a studio or one-bedroom unit and 1,000 square feet for units with two or more bedrooms, and an attached ADU is also limited to 50 percent of the main home’s floor area.

The code adds that lot coverage, open space and front setback rules cannot force an ADU below 800 square feet. An ADU may not exceed 10 percent of the lot area, subject to that same 800 square foot floor. The minimum ADU is 150 square feet.

A detached ADU on a single-family lot may not exceed 18 feet, with up to two more feet to match the main roof pitch, and 16 feet if the lot also has a JADU.

On a multifamily lot the limit is 16 feet, rising to 18 if the building has more than one story or is within half a mile walking distance of a major transit stop, again with up to two feet for roof pitch.

An attached ADU may not exceed 25 feet or the zone’s limit for the main home, whichever is lower, and may not exceed two stories.

Setbacks, spacing and design standards

These ADUs need four-foot side and rear setbacks and must meet the front setback of the zone, with no setback when built in the same location and to the same dimensions as an existing structure. A new detached ADU must be at least five feet from the main dwelling.

The city also sets objective design standards: exterior materials and colors and the roof pitch must match the main home, except where a different pitch is needed for solar panels; windows and doors may not have a direct line of sight into an adjoining residential property unless screened by fencing, landscaping or privacy glass; two-story detached units must orient stairs, decks, doors and windows to the interior of the lot or an alley; only one curb cut is allowed per parcel; exterior lighting must be shielded and directed downward; and the main home and the ADU must each have at least 15 by 15 feet of usable private yard, subject to the 800 square foot protection. A complete application must include samples of colors, materials and screening plants.

Parking, fire sprinklers, utilities and fees

Parking is one space per ADU or per bedroom, whichever is less, in addition to the main home’s parking. Tandem parking is allowed unless the city finds it infeasible because of site, topography or fire and life safety conditions.

No parking is required if the ADU is within half a mile walking distance of public transit, is in a historic district, is part of the main residence or an accessory structure, is where on-street permits are required but not offered to the occupant, or has a car-share vehicle within one block.

When a garage is converted to a JADU, on-site replacement parking is required, though it need not be covered.

Fire sprinklers are required in an ADU or JADU only if they are required in the main home, and building an ADU does not trigger sprinklers in the main home. No passageway is required.

Units within an existing home or accessory structure do not need new utility connections or related fees, and new attached or detached ADUs pay water and sewer connection charges proportionate to their burden.

No development impact fees apply to an ADU under 750 square feet, and larger units pay them in proportion to the main home’s size. Santa Maria’s Building Division can be reached at (805) 925-0951.

Owner occupancy, covenants, rentals and legalizing older units

For a JADU, the owner must live in either the main home or the JADU, and the city’s Zoning Administrator can end the JADU’s approval if neither is owner-occupied.

A covenant agreement must be recorded with the Santa Barbara County Recorder before the building permit issues, stating that the JADU cannot be sold separately, is limited to its approved size, requires owner residence, binds later owners, and ends if the JADU is removed.

An ADU or JADU can be rented for 30 days or longer. Except as Government Code section 66340 and following allows, no ADU can be sold separately from the lot and main home.

The city also chose not to allow ADUs or JADUs on parcels created under the state’s Starter Home Revitalization Act.

If a unit already exists without a permit, the code says the city will not deny an ADU or JADU application because of a nonconforming zoning condition, building code violation or unpermitted structure that does not threaten public health and safety and is not affected by the work.

For an unpermitted ADU or JADU built before January 1, 2020, the city may not deny a permit to legalize it because it violates certain building standards or the state ADU law, with exceptions for substandard buildings and for corrections needed to meet Health and Safety Code section 17920.3.

See our Santa Maria permits guide and code enforcement guide for the rest of the process.

ADUs, conversions and selling a Santa Maria house

A permitted ADU can be a selling point, while an unpermitted garage conversion or backyard unit can complicate financing and disclosure. If you own a unit with no permit history, check the city’s records and ask the Building Division what legalizing it would involve.

Our statewide guide to selling as-is with unpermitted work explains disclosure, and the capital gains guide covers tax questions on the sale. A cash buyer can purchase the property as it stands, with or without permits, so you do not have to finish or legalize the unit first.

How to sell a house in Santa Maria

Find out whether any open case, unpermitted work or permit history is on file for your property.
Gather notices, permits, plans and inspection records.
Request a no-obligation cash offer for the property as it stands.
Choose your closing date.
Close with no repairs or permit cleanup required.

Own a Santa Maria home with an unpermitted unit? Sell as-is for cash.

Get My Cash Offer

Frequently asked questions

How big can an ADU be in Santa Maria?

A limited detached ADU can be up to 800 square feet. Other ADUs can be up to 850 square feet for a studio or one bedroom and 1,000 square feet for two or more bedrooms, with attached units also limited to 50 percent of the main home. A JADU is up to 500.

How far must a Santa Maria ADU be from the property line?

Four feet from side and rear property lines, with no setback needed when the unit replaces an existing structure in the same location and dimensions. New detached ADUs must also be at least five feet from the main dwelling.

Does a Santa Maria ADU need parking?

One space per ADU or per bedroom, whichever is less, unless an exception applies, such as being within half a mile of transit or being part of the main residence or an accessory structure.

How long does ADU approval take in Santa Maria?

The city must approve or deny a complete application within 60 days, and a complete application not acted on in that time is deemed approved unless the applicant asked for a delay.

Can I rent my Santa Maria ADU as a short-term rental?

No. The code allows rental of an ADU or JADU for terms of not less than 30 days.

Can I sell my Santa Maria home if the ADU is unpermitted?

Yes. You can disclose it and sell as-is, including to a cash buyer who buys the home in its current condition.

More guides

Sources

This guide is general information from public sources, not legal advice. Confirm current rules with the City of Santa Maria.