ADU rules in Pismo Beach

Detached ADUs are allowed on lots zoned for single-family or multifamily residential use with an existing or planned home, with no minimum lot size. Inside the coastal zone (about two-thirds of the city) the certified 1983 Coastal Zoning Code Chapter 17.117 governs; outside it the city told HCD in 2025 that it applies state ADU law instead of its 2020 section 17.38.155, which carries the same exclusions. Both texts bar ADUs in mobile home parks and subdivisions and RV parks, in the R-1 zone above Longview Avenue and Stratford Street in Pismo Heights (a single-access, very high fire hazard area of about 100 coastal-zone homes) and on slopes over 20 percent. The local limit of one ADU plus one JADU per home yields to Gov. Code 66323(a), which adds a detached new-construction unit of up to 800 sq ft beside a conversion ADU and a JADU, and allows up to eight detached ADUs at an existing multifamily building where the local text says two.

Attached ADUs (sharing at least one wall with the home), conversion ADUs (any part of a legal home, accessory structure or garage, with up to 150 sq ft of additions) and JADUs of up to 500 sq ft inside a single-family home are allowed under the same rules and exclusions as detached units. A structure built without permits cannot be converted and is processed as a new construction ADU (17.117.030.D). At multifamily buildings, conversion ADUs in non-living space (storage rooms, attics, basements, garages) are allowed for up to 25 percent of the units, matching Gov. Code 66323(a)(3). A JADU may share the home's bathroom but needs an efficiency kitchen and a separate entrance.

Inside the coastal zone, Chapter 17.117 caps a new construction ADU at 850 sq ft (studio or one bedroom) or 1,000 sq ft (two bedrooms), or 50 percent of the primary home if that is smaller, but always allows at least 800 sq ft regardless of lot coverage or floor area limits; conversion ADUs have no cap and JADUs top out at 500 sq ft. Height follows the zoning district but not less than 16 ft unless the LCP sets a lower view-protection limit (15 ft in the Sunset Palisades area, which HCD and the Coastal Commission accepted in 2021). Outside the coastal zone the codified 17.38.155 (the same caps plus a 50 percent cap on conversions) is the ordinance HCD found noncompliant, and the city told HCD it uses state law instead, so the state standards apply: 1,200 sq ft for a detached unit and 50 percent of the existing home for an attached one (Gov. Code 66314(d)(4)-(5)), never less than 800 sq ft (66321(b)(3)); the city ADU page itself lists 'ADU Maximum of 1200 square feet'. Every residential lot also qualifies for the Gov. Code 66323 state-exempt units (an 800 sq ft detached unit at 16 ft, uncapped conversions within existing space).

No for ADUs anywhere in the city; a JADU needs an owner living on site only when it shares the home's bathroom. Both codified texts still impose owner residency (the owner must live in the home, the ADU or the JADU, shown by a homeowner's property tax exemption, with a recorded deed restriction) on every JADU and on every ADU not permitted between January 1, 2020 and January 1, 2025, and the city ADU page FAQ repeats the rule. That 2025 cutoff tracked a temporary state moratorium; current Gov. Code 66315 bars any owner-occupant requirement on an ADU, and 66333(b) allows JADU owner occupancy only where sanitation is shared. The Coastal Act savings clause (66329(a)) does not reach the rule, which protects no coastal resource. A deed restriction against selling a JADU separately remains required (66333(c)).

Inside the coastal zone, Chapter 17.117 requires one off-street space for a studio or one-bedroom ADU and two for a two-bedroom ADU on top of the home's parking (tandem and setback parking allowed), and garage spaces lost to an ADU conversion must be replaced. The state exemptions (within half a mile walking distance of transit, historic district, unit inside the home or an accessory structure, on-street permits not offered, car share within a block) waive it, except on properties west of US 101 within a quarter mile walking distance of a vertical beach access point, the Coastal Trail, a coastal park or a coastal view area, where the Coastal Commission certified the requirement in 2021 to protect visitor beach parking; the city FAQ summarizes this as parking required for ADUs west (oceanside) of Highway 101. Outside the coastal zone the inoperative 1998 section's one-space rule gives way to state law: at most one space per ADU or bedroom, whichever is less, waived in all six Gov. Code 66322(a) cases. JADUs never need parking.

Ministerial everywhere. Inside the coastal zone every ADU and JADU needs an administrative coastal development permit plus a building permit, with the public hearing waived: in the coastal appeal zone neighbors within 300 ft get mailed notice at least ten days before the permit issues, and elsewhere in the coastal zone the Director's action is final with notice afterward (fees $783, or $302 for a small addition, plus a $240 mailing fee). Outside the coastal zone a zoning clearance ($185) and a building permit are required. Complete applications must be acted on within 60 days (Gov. Code 66317; 66329(a) for coastal permits). The codified line that appeal-zone approvals can be appealed to the Coastal Commission within ten days has been overridden since 10-10-2025 by 66329(c), which makes a local ADU coastal permit decision unappealable under Public Resources Code 30603.

Both codes apply one occupancy standard to every ADU and JADU in the city: no short-term rental use of less than 30 days, and the units must be occupied for terms longer than 30 days, which makes 31 days the practical minimum (one day stricter than the 30-day floor Gov. Code 66315 allows for ordinary ADUs, and the same as the longer-than-30-days rule of 66323(e) and 66333(g) for state-exempt units and JADUs). Short-term rentals are frozen citywide anyway: Ord. O-2023-006 (introduced 11-7-2023, adopted 12-5-2023) capped short-term rental and homestay licenses at the 28 then in effect, accepts no new applications and phases them out by attrition (PBMC 5.22.130.A), and vacation rentals are confined to the downtown C-1, RR and R-4 zones. ADUs and JADUs cannot be sold separately from the home except under the qualified-nonprofit path (the code cites legacy 65852.26, now 66341), and the city has not opted into 66342 ADU condominiums. A business license is needed only by operators of three or more rental units (PBMC 5.04.180).