ADU rules in Elk Grove

A detached ADU is a permitted ('P') use in every agricultural (AG-80, AG-20), agricultural-residential (AR-1 to AR-10) and residential (RD-1 to RD-40) district and in the GC, VCMU and RMU commercial and mixed-use districts (Table 23.27-1), and Chapter 23.90 allows ADUs on any lot zoned for single-family, multifamily or mixed use that has a proposed or existing dwelling. A single-family lot may add one detached new-construction ADU of up to 1,200 sq ft, which may be combined with a JADU and, under Gov. Code 66323(a) ('any combination'), with a conversion ADU inside existing space; a lot with existing multifamily housing may add up to eight detached ADUs (never more than its existing unit count) and a lot with proposed multifamily housing up to two. The Special Planning Areas that hold much of the newer housing defer to Chapter 23.90 (the Southeast Policy Area SPA permits ADUs in its MUR, MUV, ER, LDR, MDR and HDR designations); ADUs are not listed in the office, industrial, LC, SC and AC districts, which allow no housing.

ADUs may be attached to or built within the proposed or existing primary dwelling, including attached garages and storage areas, or within an accessory structure (23.90.040(A)). A conversion of existing space needs no new setbacks and may add up to 150 sq ft beyond the existing footprint only for ingress and egress (23.90.040(D)(1), (G)(1)); an attached addition follows the attached size cap and the 4-ft side and rear setbacks for new construction. On multifamily lots at least one ADU, and up to 25 percent of the existing unit count, may be carved from non-livable space such as storage rooms, garages, attics or basements (23.90.040(D)(4)). A JADU of up to 500 sq ft is also allowed within the walls of a single-family home, including an attached garage, with its own entrance and an efficiency kitchen; one per lot (23.90.050).

EGMC 23.90.040(F), rewritten by Ord. 13-2025 (effective 7-25-2025), caps a detached ADU at 1,200 sq ft of total floor area and an attached ADU at the greater of 50 percent of the existing primary dwelling's floor area or 850 sq ft (one bedroom or less) / 1,000 sq ft (more than one bedroom); every ADU must be at least 150 sq ft and a JADU no more than 500 sq ft. Heights under 23.90.040(H): 16 ft for a detached ADU in general, or up to the zoning district's height limit if it sits inside the allowed building envelope outside the required yards; 18 ft plus 2 ft for a roof pitch matching the house within half a mile walking distance of a major transit stop or high-quality transit corridor; 18 ft on a lot with a multistory multifamily building; 30 ft in the agricultural and agricultural-residential districts; attached ADUs 25 ft or the height of the house, whichever is greater. The code does not say how 'total floor area' is measured, while the Gov. Code 66321(b) floors (850/1,000 sq ft, and an 800 sq ft unit with 4-ft side and rear setbacks) have been measured in interior livable space since January 1, 2026; the city's caps sit at or above those floors. An existing house may be redesignated as the ADU when a new primary home is built if it fits within these caps (23.90.030(B)).

Chapter 23.90 imposes no owner-occupancy requirement on ADUs, and the city's ADU page answers 'No, both the existing house and the ADU can be rental units'; Gov. Code 66315 bars such a condition for ADUs in any case. The only owner-occupancy rule is for JADUs: 23.90.050(G), as re-enacted by Ord. 13-2025, requires the owner to live in either the house or the JADU (governmental agencies, land trusts and housing organizations excepted) and a recorded deed restriction. Since January 1, 2026, Gov. Code 66333(b) (AB 1154) allows JADU owner occupancy only where the JADU shares sanitation facilities with the house, and 66339.5 makes the state article supersede conflicting local text, so a JADU with its own bathroom carries no owner-occupancy requirement even though the codified text and the city page still state one.

EGMC 23.90.040(J) requires 'one (1) additional off-street parking space for each bedroom' unless the ADU is within half a mile walking distance of public transit, including any bus stop, in an architecturally and historically significant historic district, part of the existing house or an existing accessory structure, where on-street permits are required but unavailable, within one block of a car share vehicle, or permitted together with a new primary dwelling on a lot meeting another criterion. Table 23.58-2 lists '1 space/unit, or as otherwise required by EGMC Chapter 23.90' with a two-space maximum; spaces may be tandem on an existing driveway and in setbacks (23.90.040(K)), and JADUs need none (23.90.050(F)). State law caps any requirement at one space per unit or per bedroom, whichever is less (Gov. Code 66314(d)(10)(A)), so a two-bedroom ADU owes at most one space and a studio none; units on the state-exempt path (conversions, a detached unit of up to 800 sq ft of livable space with 4-ft setbacks, multifamily units) owe none under 66323(b), and a garage, carport or uncovered space demolished or converted for an ADU need not be replaced (66314(d)(11)). The city's own FAQ says 'Generally, off-street parking is not required for ADUs'; in practice a space is owed only for an addition or a detached unit over 800 sq ft more than half a mile from any bus stop.

ADUs are allowed 'subject to zoning clearance/plan check review' (23.90.030(A)) and are 'permitted on single-family and multifamily residential parcels by the Community Development Director when the following conditions are met' (23.90.040); zoning clearance is an administrative plan check run inside building permit review with no separate application (23.16.020), and Table 23.27-1 lists ADUs as 'P' (permitted by right) wherever they are allowed. Gov. Code 66317 requires a ministerial decision without a hearing, a completeness determination within 15 business days and a decision within 60 days of a complete application. Applications go through the Building Division's electronic Filedrop, with outside-agency releases from Cosumnes Fire, Sacramento County Technical Resources and, for well or septic lots, Sacramento County Environmental Management; the city also offers three pre-approved detached plans (435, 625 and 746 sq ft) and designers' master plans for faster review.

EGMC 23.90.040(I) lets an ADU be rented separately from the primary unit for 'terms of thirty (30) days or longer'; Ord. 13-2025 loosened this from 'longer than thirty (30) days', which Gov. Code 66315 permits for units approved under the local standards ('rentals of terms 30 days or longer'). Units created on the state-exempt path of Gov. Code 66323 (conversions, the detached unit of up to 800 sq ft, multifamily ADUs) must be rented for terms longer than 30 days (66323(e)), as must JADUs (66333(g), effective January 1, 2026). Short-term rentals (stays of two nights to 30 days) need a three-year city license, 12 percent transient occupancy tax and a two-night minimum (Chapter 4.38; Table 23.27-1 notes), but the rental-term rule keeps ADUs out of that market. A landlord renting a property with 16 or fewer units must register it with the city (16.20.1218). An ADU may not be sold separately except under the qualified-nonprofit rule the code still cites by its legacy number 65852.26 (now Gov. Code 66341) (23.90.040(L)); Elk Grove has no Gov. Code 66342 ADU-condominium ordinance, and a JADU may never be sold separately (23.90.050(G)).