Long Beach | ADUs and SB 9

Long Beach ADUs and SB 9: State ADU Law Applied Directly, and Two-Unit Projects in R-1

An accessory dwelling unit (ADU) is a second, smaller home on the same lot as a house or apartment building, with its own kitchen and bathroom. A junior ADU is a unit of 500 square feet or less made from space inside a house. SB 9 is the 2021 state law that allows a second main home, or a lot split, on a single-family lot. Long Beach applies all three directly from state law and explains how in its own bulletin and checklist. This page sets out those rules.

Long Beach Applies State ADU Law Directly

The Municipal Code still prints an ADU section, 21.51.276, and Table 31-1 still points to it. The City has set that section aside. Its ADU and SB 9 page says: "Long Beach currently applies state ADU law directly, as a local ordinance is still in development," and "Please note that Long Beach Municipal Code 21.51.276 no longer applies, and the City is administering state ADU law directly until a new local ordinance is adopted." The Planning ADU Bulletin says the same: "The City of Long Beach does not currently have an adopted local ADU ordinance as of the date of this Bulletin. Therefore, all ADU and JADU projects are reviewed strictly in accordance with State ADU law."

State law supports that reading. Government Code 66316 says that if a city's ADU ordinance "fails to meet the requirements of this article, that ordinance shall be null and void and that agency shall thereafter apply the standards established in this article." The printed section is stricter than state law in several places, which shows why it fell:

• Minimum lot size. Section 21.51.276 sets a 4,800 square foot minimum lot. Government Code 66321 bars limits on "minimum lot size" that do not permit an ADU "with at least 800 square feet of interior livable space."
• Owner living on site. The section required the owner to "reside either in the primary dwelling or the accessory dwelling unit." Government Code 66315 bars "an owner-occupant requirement."
• Size. The section capped an ADU at "50% of GFA of the primary dwelling, or 800 sq. ft., whichever is less." The statute forbids a size based on a percentage of the house that falls below 800 square feet.
• Time. The section gave the City 120 days to decide. Government Code 66317 requires a decision "within 60 days," or the application "shall be deemed approved."

So for an owner today, the bulletin is the working rulebook. It says it "summarizes the requirements of State ADU law for the convenience of ADU builders" and that "Upon adoption of a local ADU ordinance by the City Council, this Bulletin shall become ineffective." Check the bulletin date before you design, since a new City ordinance would replace it.

How Many ADUs on a House Lot

The bulletin starts with lot type. "A single-family dwelling lot has one or more detached single-family dwellings and no multi-family dwellings. A multi-family dwelling has two or more principal dwelling units in one building, or as attached buildings." A lot with a duplex is therefore a multi-family lot for ADU purposes. For a single-family lot, the bulletin says: "one conversion ADU and one detached new construction ADU can be permitted, in addition to one JADU."

Source: City of Long Beach Planning ADU Bulletin, Table 1 and its notes. The three conversion and attached rows share the one conversion ADU.

A conversion ADU turns existing space into a home. The bulletin counts a rebuild as a conversion when it is "limited to the same location and same dimensions as the rebuilt building." For a garage or other accessory building, "An addition to an existing accessory building is permitted only for ingress and egress, and is limited to 150 sq. ft." The bulletin's example is a stairway. The attached ADU size limit "applies only to the addition and not to the converted area of the single-family dwelling."

The junior ADU has its own rules. It is a conversion "only of portion of existing primary dwelling or attached garage," and "No addition is permitted for a JADU." The bulletin adds: "Owner occupancy of the single-family dwelling or the JADU only is required if the JADU shares a bathroom with the primary dwelling," and "A JADU always must have its own kitchen." That matches Government Code 66333, which drops the owner rule "if the junior accessory dwelling unit has separate sanitation facilities."

Every ADU or junior ADU "must be at least 150 sq. ft. in size," the minimum for an efficiency unit under state health law. And "No standards for lot coverage, open space, or floor area ratio apply" to the ADU types in the bulletin. ADU floor area "is measured only to the interior walls," while every other standard on the lot still uses gross floor area measured to the outside of the walls.

ADUs on Duplex and Apartment Lots

Long Beach has many older duplexes, triplexes and small apartment buildings, and state law lets each of them add ADUs. The bulletin's multi-family rows read:

Source: City of Long Beach Planning ADU Bulletin, Table 1, Multi-Family Lots.

By VanPlex arithmetic, an existing fourplex can add up to 4 detached ADUs (the lesser of 8 and 4) and 1 converted ADU (the greater of 1 and 25 percent of 4), for 9 homes on the lot. Detached ADUs here may include "new construction, conversion of accessory building(s), or addition to and conversion of accessory building(s)." For converted space inside the building, "No addition is permitted." A lot with both a house and an apartment building gets each set of rules for its own building, but "an SFD ADU cannot be applied to the MFD or vice versa."

Height, Setbacks and Parking for ADUs

Table 2 of the bulletin sets height. A new detached ADU may be 16 feet tall unless an exception applies. It may be "18 feet" with "Transit proximity," defined as "within one-half mile walking distance of a major transit or a high-quality transit corridor," and up to 2 more feet "to match existing sloped roof of primary dwelling." A new detached ADU on a lot with an existing multi-story, multi-family building also gets 18 feet. An attached ADU on a house lot may reach "25 feet/2 stories, or zoning height limit, whichever is less." A conversion keeps the existing building height. These figures track Government Code 66321, which sets 16 and 18 foot floors. The City's SB 9 Parking Exemption and ADU Height Exception Map, marked "As of April 2026," shows the half-mile walksheds.

Table 3 sets setbacks for new construction: the front setback is the zoning district's, the side setback is "4 feet or per zoning district, whichever is less," and the rear setback is 4 feet, measured "to centerline of adjacent alley where such exists." The bulletin adds: "If there is no other way to accommodate an ADU up to 800 sq. ft. on the lot, an ADU may encroach into the required front yard setback." A conversion keeps its existing setbacks if they are safe for fire and life safety.

The bulletin requires no parking in any of these cases:

• an ADU within one-half mile walking distance of any transit stop;
• an ADU in a historic district;
• an ADU converted from part of the house or an accessory building;
• where on-street parking permits are required on the street but not offered to the ADU occupant;
• "For an ADU within one-half mile of a car share vehicle";
• an ADU filed with a new house or apartment building when one of the cases above applies;
• any junior ADU;
• an ADU in the Parking Exempt Area set by Section 21.41.175.

The car share line is wider than state law. Government Code 66322 exempts an ADU "When there is a car share vehicle located within one block." The City's half-mile test reaches more lots than the statute's one block, which works in the owner's favor.

Coastal, Historic and Permit Steps for ADUs

Two areas add a step. "Any ADU or JADU project in the Coastal Zone is required to obtain an Administrative Local Coastal Development Permit (LCDP). No public hearing is required." And "Any ADU or JADU project in a historic district, or at a designated historic landmark property, must obtain a Certificate of Appropriateness (COA)," also with no hearing. Both are filed at the same time as the building permit. Government Code 66329 says a city "shall not be required to hold public hearings for coastal development permit applications for accessory dwelling units." The coastal zone and historic districts page explains both permits.

The building permit itself is filed in person. The City page says "All construction documents and related permit applications must be submitted in person, and applicable plan check fees are due the same day. Online submissions are not available at this time." Some ADUs qualify for over-the-counter review, but "projects located in a Historic District, within the Coastal Zone, or involving major structural engineering are not eligible." The City's Pre-Approved Accessory Dwelling Unit Program offers ready plans, "available for new construction only (not for conversions of existing space)." The City page also notes that "Long Beach ranks as the highest per-capita producer of ADUs in California," by the City's own account.

SB 9 Two-Unit Projects in Long Beach

The City calls an SB 9 home a "Two-Unit Residential Development (SB 9 unit)," which "allows the construction of a second principal dwelling unit on properties zoned R-1 (single-family)." It may be "a detached second single-family dwelling, or as an attached second unit (duplex)," and "If the lot is vacant, two new SB 9 units may be built instead." The City adds that "an Urban Lot Split is not required to build an SB 9 unit," and that "an SB 9 unit is classified as a principal dwelling and is therefore subject to the same fees and regulations as any other new home."

The SB 9 Project Eligibility Checklist (Form PZ007, revised 9/22/26) is filed with the building plans. Each item is answered yes or no. The main tests are:

• no more than "Two (2) principal dwelling units, plus one ADU and one JADU for projects not involving an urban lot split," or two units of any type per parcel after a split;
• "The parcel is located entirely within a Single-Family (R-1) Zoning District";
• the site is outside wetlands, hazardous waste sites, unmitigated flood zones and floodways, conservation land and protected habitat, and earthquake fault zones unless built to the seismic code;
• no demolition or alteration of more than 25 percent of the exterior walls of rent-restricted or rent-controlled housing, or of housing "occupied by a tenant in the last three years";
• no withdrawal of rent-controlled homes from the rental market on the lot within 15 years;
• not a contributing structure in a historic district and not a designated landmark;
• rentals longer than 30 days, a coastal approval where needed, and no fewer homes than the General Plan allows on the site.

Item 9 sets the building rules for each unit: at least 150 square feet, a real kitchen with a "Built-in or permanent cooktop" ("A microwave or hot plate is not sufficient"), at least a three-quarter bathroom, the district front setback, and four-foot side and rear setbacks. Lot coverage, open space and floor area ratio follow the district, but "If compliance with Lot Coverage, Open Space, or FAR standards would preclude development of principal unit(s) of at least 800 sq. ft. in area, then principal unit(s) of 800 sq. ft. in area shall be permitted." Parking is "One parking space is provided per unit" unless the lot is within half a mile walking distance of a high-quality transit corridor or major transit stop, or a car share vehicle is within one block.

These tests follow Government Code 65852.21, which requires a decision "within 60 days from the date the local agency receives a completed application" and bars standards that "would physically preclude either of the two units from being at least 800 square feet in floor area." The checklist itself says "No project is approved (either expressly or implied) until building permits are issued."

SB 9 in Historic Districts: Two City Documents

The City page says "SB 9 units are allowed for lots with non-contributing structures in Historic Districts." A non-contributing structure is a building in a historic district that the district ordinance does not count as historic, such as a newer house. The checklist bars "A contributing structure within a historic district" and any property "individually designated or listed as a city landmark." Read together, the two documents allow an SB 9 unit on a lot whose house is non-contributing. The urban lot split is narrower: Section 20.18.070 bars it on any lot "within a City Historic District," contributing or not. See the lots and subdivisions page for the split.

Where to Go Next

Related on VanPlex: the Long Beach overview, the California ADU law page and SB 9 in California.

Frequently Asked Questions

Official sources (checked October 2026)