ADU rules in Carson

Yes. Since about April 18, 2024 the ADU rules for Carson's residential and mixed-use zones are Part 3-B, Division 10 (Secs. 93110.1 to 93110.4) of the New Zoning Code: Phase 1 adopted by Ord. No. 24-2405, and Table 9211.2 lists the accessory dwelling unit as 'P' (permitted subject to a zoning compliance determination) in all four residential districts (LDR, LMX, MDR and HDR). Sec. 93110.4.B allows one detached or one attached new-construction ADU on a lot with a single-unit dwelling, combinable with a JADU, and Sec. 93110.4.D.5 allows up to two detached new-construction ADUs on a lot with an existing or proposed multifamily dwelling. New units need only 4-foot side and rear setbacks and there is no minimum lot size. The local 'only one category may be used per lot' rule and the two-unit multifamily cap yield to Gov. Code 66323(a) as amended by SB 543 (any combination of the listed units; up to eight detached ADUs beside an existing multifamily building, never more than its existing unit count).

Yes. Sec. 93110.4.A.1 allows one ADU and one JADU inside the space of a proposed or existing single-unit dwelling (including an attached garage), or an ADU inside an existing accessory structure plus up to 150 square feet of expansion, each with independent exterior access, and Sec. 93110.4.B allows one attached new-construction ADU in place of a detached one. On multifamily lots, ADUs may be carved out of non-livable space such as storage rooms, boiler rooms, attics, basements and garages, up to 25 percent of the existing units with at least one allowed (Sec. 93110.4.D). JADUs (up to 500 square feet) must meet the state JADU statute. Attached ADUs may rise to 25 feet or the zone's primary-dwelling limit, whichever is lower (20 feet in LDR), and no more than two stories.

Sec. 93110.4.F.4 caps a detached ADU at 1,200 square feet and an attached ADU at 850 square feet for a studio or one bedroom and 1,000 square feet for more than one bedroom, or 50 percent of the existing primary dwelling's floor area, whichever is smaller; ADUs converted from existing space are exempt from the caps and a JADU is capped at 500 square feet. The code bars open space, site coverage and FAR rules from cutting an ADU below 800 square feet, and Gov. Code 66321(b)(3) extends that 800-square-foot guarantee to the 50 percent rule, which the Phase 1 text (unlike the old Sec. 9122.1.E.4.d) no longer names. Heights: Sec. 93110.4.F.3 sets 18 feet (plus 2 feet for a roof pitch matching the house) for a detached unit within a half mile of a major transit stop or high-quality transit corridor, 18 feet beside a multifamily building, 25 feet or the primary-dwelling limit for an attached unit, and two stories over a detached garage; it sets no height for other detached units, so the state floor of 16 feet (66321(b)(4)(A)) governs. A state-exempt detached unit under 66323(a)(2) may be held to 800 square feet of livable space.

No. Division 10 imposes no owner-occupancy requirement on ADUs, and Gov. Code 66315 bars one. For JADUs, Sec. 93110.4.A.1.e defers to the state JADU statute (cited as 65852.22, now 66333), and since January 1, 2026, 66333(b) requires the owner to live in the house only when the JADU shares sanitation facilities with it. The pre-2024 Old Code text still printed on eCode360 (Sec. 9122.1.G.3, Ord. 22-2211) carries a universal JADU owner-occupancy rule, superseded in residential zones by Ord. 24-2405 and overridden by 66333(b) in any case. The city's December 2021 ADU application packet still describes ADUs on lots 'with an existing single owner occupied dwelling' and a universal JADU residency rule; neither is current law.

Sec. 93110.4.F.9 requires no parking for a JADU and at most one space per ADU, which may be tandem or on an existing driveway (but not in a rear setback abutting an alley, or in the front setback unless the driveway there is at least 20 feet deep); Table 9316.4 lists '0-1 per unit, which may be tandem'. No space is required for an ADU inside the existing or proposed home or an accessory structure, within a half-mile walk of public transit (defined to include a bus stop or train station served by fixed-route, set-fare service),in an architecturally and historically significant historic district, where on-street permits are required but not offered, or within one block of a car-share vehicle, and garage or carport spaces lost to an ADU need not be replaced (Sec. 93110.4.F.10). The local exemption list omits Gov. Code 66322(a)(6) (an ADU applied for with a new single-family or multifamily dwelling), and the flat one-space rule reaches studios and state-exempt units, which 66314(d)(10)(A) (one space per unit or per bedroom, whichever is less) and 66323(b) do not allow; state law controls.

Permitted. Sec. 93110.3.A requires any ADU or JADU that meets Division 10 to be 'approved ministerially without discretionary review or public hearing', within 60 days of a complete application (Sec. 93110.3.B), and Table 9211.2 makes the ADU a 'P' use subject only to a zoning compliance determination, the Director's ministerial review under Secs. 9413.1 to 9413.3 (appealable to the Planning Commission). The city's posted ADU application has the Planning Division issue an ADU approval before the applicant submits for building plan check. Since Ord. Nos. 25-2515U and 25-2514 (July 2025), every Director approval, including a ministerial zoning compliance review, needs the City Manager's prior concurrence, and any one council member may call a Director decision up for review within the appeal period; a review hearing on an ADU would collide with Gov. Code 66317(a)(1), and no record shows one has been held.

Sec. 93110.4.F.11.c bars renting an ADU or JADU 'for periods of 30 days or less', so every rental must run at least 31 days: that matches the longer-than-30-day terms Gov. Code 66323(e) and 66333(g) require for state-exempt units and JADUs, and is one day stricter than the 30-day minimum 66315 lets a city impose on other ADUs; longer rentals face no city registration or rent-control program. Division 62 (Secs. 93162.1 to 93162.3) separately prohibits short-term rentals (30 consecutive days or less, including advertising or offering one) in every zoning district citywide 'without exception'. Urgency Ord. No. 25-2503U (January 21, 2025) suspended that ban in residential and mixed-use zones for nine months to house wildfire evacuees; it sunset around October 21, 2025, and no extension appears in council minutes through September 1, 2026. A deed restriction recorded before the building permit notices the rental and conveyance limits, and Sec. 93110.4.F.12 allows separate sale only under 65852.26 (now 66341, qualified nonprofits); Carson has not opted into 66342 ADU condominiums.