ADUs in Lemon Grove, CA
✓ Verified November 1, 2026 Rules, fees, and timelines below were verified November 1, 2026. Anything marked “confirm” or “to verify” is still open.
State HCD itself reviewed Lemon Grove's ordinance and found it noncompliant. HCD's letter (December 10, 2025) reviewed LGMC §17.24.060 “updated in 2022” and found it fails state ADU law on 16 points, with a city response due January 9, 2026. Whether the city has since amended is unconfirmed — the code text still shows the 2022 text and the stale citations HCD flagged. Where the code conflicts with state law, state law controls. Confirm current rules with the Planning Division before designing.
ADUs and JADUs are permitted only in zones RL, RLM, RM, RMH, RP, and CG — not in other zones. Properties in Special Treatment Area I are subject to the Downtown Village Specific Plan — check both per parcel.
The City has its own ADU ordinance (Lemon Grove Municipal Code §17.24.060, Ord. 461 §1, 2022) and does not defer to state law — but see the HCD flag above. Planning Division, 3232 Main Street, (619) 825-3805.
Does it apply to my lot? — address check
Enter a San Diego County street address. The checker geocodes it and checks public transit stops nearby. Privacy: your typed address goes directly from your browser to OpenStreetMap's free Nominatim geocoder and the public SanGIS transit-stops layer. It never touches an ADUKey server — ADUKey has no server endpoint for this, so there is nothing to send it to.
Parking-exemption rule: no parking required within a 1/2-mile walking distance of public transit (bus stops included). Straight-line distance is measured first: a straight-line miss is definitive, a straight-line hit is provisional until the walking route is checked.
What you can build
| Rule | What applies | Note |
|---|---|---|
| ADU size | Minimum 150 sq ft; maximum 100% of the primary dwelling or 1,200 sq ft, whichever is less; if the primary is under 800 sq ft, an 800 sq ft ADU is permitted; conversion of an existing accessory building has no max size if expansion is ≤150 sq ft | |
| State guarantee | Standards must not prohibit an ADU up to 800 sq ft with 4 ft side and rear yards | HCD finding 8: the code's 16-ft height cap on exemption units must go — state height allowances apply. |
| Height | Detached 16 ft; 18 ft within one-half mile walking distance of a major transit stop or high-quality transit corridor, +2 ft to match the primary roof pitch; attached 25 ft; multifamily detached 18 ft; conversion of an existing accessory building has no height limit if expansion ≤150 sq ft | |
| Setbacks | Front per underlying zone (handout table: 25 ft; ADUs may be permitted in front setbacks if nowhere else to place them); street-side, side, and rear 4 ft or zone, whichever is less; conversions with expansion ≤150 sq ft: no setback | HCD finding 12: setbacks larger than 4 ft (except fire/safety) must not apply to conversions/same-footprint rebuilds — the code's “primary's setbacks” rule for internal/JADU units is flagged. |
| Building separation | 10 ft minimum from primary and accessory structures (handout); attached ADUs must share a common wall with the primary | |
| Junior ADU (JADU) | 150–500 sq ft, entirely within an existing/proposed single-family residence; efficiency kitchen; no expansions of existing structures; not permitted in multifamily dwellings; owner-occupancy required; deed restriction required | Owner-occupancy exception currency unconfirmed (AB 1154 ties it to whether the JADU has its own bathroom); HCD finding 7: the deed-restriction clause must be fixed. |
| Unit counts (code text) | Single-family lot: 1 ADU + 1 JADU (code, 2022); lot with more than one single-family dwelling: 1 internal or detached ADU per lot (code); multifamily: up to 2 detached ADUs + conversion of non-living space to ≥1 or up to 25% of units (code) | Code caps are wrong under current state law — HCD findings 4–6 and SB 1211 correct them; do not present “1 ADU + 1 JADU” as the final word. Single-family: §66323 allows a converted ADU + a detached new-construction ADU + a JADU. Existing multifamily: up to 8 detached ADUs, not exceeding the existing unit count. |
| Parking | 1 off-street space per ADU except: within ½ mile walking distance of public transit (bus stops and train stations included); in a significant historic district; part of the primary/accessory structure; permit parking required but not offered to the occupant; car-share within one block; garage conversion needs no replacement. JADUs: no additional spaces, except the flagged garage-replacement clause | HCD finding 13: the code's garage-parking replacement requirement for JADU conversions is unlawful — a JADU ordinance may not require additional parking at all. Finding 14: the code omits the concurrent-new-dwelling-application exception. |
| Minimum rental term | Longer than 30 days (state floor); city-specific enforcement to confirm | City-specific rental rule is builder-guide only — Better Place reports over 30 days and no short-term rentals. City home-sharing ordinance (Ord. 452) allows only host-on-site home-sharing; vacation rentals are prohibited citywide — that ordinance is not ADU-specific. |
| Impact fees | Exempt for ADUs under 750 sq ft; fees on larger ADUs proportional to primary dwelling size (state floor). From Jan 1, 2027 (SB 1117, builder guide), covered fees are calculated only on livable space above 750 sq ft for lots with up to two ADUs | Dollar figures (plan-check percentage, TUMF ~$2,688.21/unit, stormwater surcharge, school fees) are builder-guide only — to confirm against the Master Fee Schedule. SB 1117 is builder-reported state change. |
| Permit fees | Not published — confirm with the Planning Division | No city fee schedule confirmed; SnapADU $8–$10/sq ft estimates are not city fees and are not published here. |
| Multifamily lots | Up to 2 detached ADUs + conversion of non-living space to ≥1 or up to 25% of units (code); state law for existing multifamily: up to 8 detached, not exceeding unit count | Code figures are the 2022 text; SB 1211/HCD correction flagged — confirm current treatment with the Planning Division. |
| Design | Same/complementary style, materials, and colors as the primary; quality same or better (code — see HCD flag); no minimum lot size; no FAR, max lot coverage, or max stories; no street dedication/improvement or landscape requirements | HCD finding 16: “complementary” style and “same or exceed” quality are subjective and must be removed — only objective standards are allowed. Treat the design rule as an enforceability caveat. |
| Fire sprinklers | Not required for the ADU/JADU unless required for the primary | HCD finding 15: the code must also state ADU construction does not trigger sprinklers in the existing primary. |
| Overlays to check | No coastal zone (inland city); no Very High fire zone, ~22 acres High, ~27 acres Moderate (third-party CAL FIRE summaries); STA I / Downtown Village Specific Plan; topography is a site-specific review item for preapproved plans | Fire acreage figures are third-party summaries of CAL FIRE data (city fire-maps page not opened). Hillside and flood ADU rules: to confirm per parcel. |
Permit path
- Confirm jurisdiction, zone, and overlays with the Planning Division (3232 Main Street, (619) 825-3805). ADUs/JADUs are permitted only in zones RL, RLM, RM, RMH, RP, and CG.
- Submit. State law requires ministerial approval within 60 days or a full set of denial comments — but HCD finding 2 notes the code section as submitted contains no approval/denial procedures and must be amended to include them. Treat the 60-day rule as the state-law requirement, with the code gap flagged.
- Build. Builder guides estimate 3–6 months for approval and 10–12 months total — label those as builder estimates, not city timelines.
In-person submission is reported by builder guides only — no city-published statement of in-person-only submission was found, so confirm. Do not conflate the city's online SolarAPP+ system (solar permits, including ADU solar) with ADU permit submission.
Preapproved plans
The city's preapproved-plans program under AB 1332 (Gov. Code §65852.27) offers streamlined 30-day approval for preapproved plans. One plan set is documented: a 797 sq ft, 1-story, 2-bedroom/1-bathroom detached ADU with a 112 sq ft porch (909 sq ft building area), by YWR Architects, under the 2025 California Building Code. No changes to preapproved plans are allowed — no room reconfiguration, window relocation, or attaching to structures — to qualify for preapproved processing. The city's own disclaimer: “preapproved” is somewhat misleading, because other disciplines still review site-specific characteristics such as topography and are likely to have comments. Whether additional plan sets exist beyond this one, and cost, are to confirm — the city page invites others to submit non-site-specific plans for review, so the library may grow.
Separate sale (AB 1033)
Not adopted as of July 2025 (builder guide). The JADU deed restriction — a JADU cannot be sold separately from the primary dwelling — is consistent with non-adoption, though that provision governs JADUs specifically. Confirm, this changes fast. JADUs can never be sold separately even under AB 1033 (state law).
Transit context — and what it is not
Lemon Grove is served by the San Diego Trolley Orange Line (Massachusetts Avenue and Lemon Grove Depot stations) plus MTS bus service — relevant because the city code's parking exemption uses one-half mile walking distance of public transit including bus stops and train stations, and the site's SanGIS layer covers MTS stops county-wide. The city handout requires a proximity map to the nearest bus stop or transit center on plans, and notes parking and height are both impacted within ½ mile of transit. This is not a Transit Priority Area determination: TPA status is a separate layer and is not claimed here.
What it costs (county range, not Lemon Grove data)
Cost band $300,000–$450,000+ is a San Diego County range, not verified Lemon Grove data. Use the calculator below with your own numbers.
Rent calculator
Defaults below are EXAMPLES — editable placeholders, not verified local rent or cost data. Type your own numbers.
Verified builders in San Diego County
One metro-level profile per builder, linked from every city page they serve. Profiles are never duplicated per city, so a correction lands everywhere at once.
Frequently asked questions
Do I need parking for an ADU in Lemon Grove?
One off-street space per ADU, except: (A) within one-half mile walking distance of public transit (bus stops and train stations included); (B) within an architecturally and historically significant historic district; (C) the ADU is part of the proposed/existing primary dwelling or accessory structure; (D) on-street parking permits are required but not offered to the ADU occupant; (E) a car-share vehicle is within one block; (F) garage/carport/covered parking removed or converted for an ADU need not be replaced. Required spaces may be tandem or within setbacks. The city handout notes most ADUs are exempt, and plans must include a proximity map to the nearest bus stop or transit center. Two HCD flags: the code's requirement to replace garage parking removed for a JADU conversion is unlawful (finding 13), and the code omits the exception for applications submitted together with a new dwelling application (finding 14).
Does Lemon Grove offer preapproved ADU plans?
Yes — the city's preapproved-plans program under AB 1332 offers streamlined 30-day approval for preapproved plans. One plan set is documented: a 797 sq ft, 1-story, 2-bedroom/1-bathroom detached ADU with a 112 sq ft porch (909 sq ft building area), by YWR Architects, under the 2025 California Building Code. No changes to preapproved plans are allowed (no room reconfiguration, window relocation, or attaching to structures). The city's own disclaimer: “preapproved” is somewhat misleading — other disciplines still review site-specific characteristics like topography. Plan count beyond this one set, and cost, are to confirm.
How big can an ADU be in Lemon Grove?
ADU: minimum 150 sq ft; maximum 100% of the primary dwelling or 1,200 sq ft, whichever is less — if the primary is under 800 sq ft, an 800 sq ft ADU is permitted. Conversion of an existing accessory building has no max size if expansion is ≤150 sq ft for ingress/egress. JADU: 150–500 sq ft, entirely within the home. State law separately guarantees 800 sq ft with 4 ft setbacks; HCD finding 8 says the code's 16-ft height cap on exemption units must go and state height allowances (16/18/20 ft) apply.
Why does this page keep saying state law controls?
Why does this page say state law controls where the code differs? Because HCD's December 10, 2025 letter found §17.24.060 noncompliant on 16 points — including wrong unit caps, a missing approval procedure, an unlawful JADU parking-replacement rule, and subjective design language (“complementary” style, “same or exceed” quality) that must be removed. Until the city amends, the code figures on this page are the city's published (2022) text, and the state-law corrections are flagged beside them.
Sources
- Lemon Grove Municipal Code §17.24.060 via eCode360 (city code publisher)
- HCD ordinance review letter, December 10, 2025 — 16 noncompliance findings (state agency, primary source)
- City of Lemon Grove ADU Development Standards handout (city-published)
- City of Lemon Grove ADU page (city-published)
- City of Lemon Grove Preapproved ADU plan set, 2025 UBC, YWR Architects (city-published)
- City of Lemon Grove fire hazard safety zone maps page
- Lemon Grove ADU regulations — Better Place (builder guide, July 2025)
- Lemon Grove ADU regulations — SnapADU (builder guide)
Not legal advice. This page is a starting point, not a parcel approval. Confirm your lot with the city before you build, buy, or sign anything.
Report an outdated rule
Rules change. If something on this page no longer matches the city's current rules, tell us what changed and where you saw it. Reporting is not wired to a destination yet — your note stays on this page and is not sent anywhere.