ADU rules in Carlsbad

Carlsbad's zoning ordinance flatly bars a dwelling unit in any detached accessory building: section 56-70(f)(7) says that except as otherwise expressly allowed, no dwelling unit shall be located in any accessory structure or building, and that subsection's own lead-in applies its standards to all accessory uses and structures in all districts. Nothing in Chapter 56 expressly allows one, because the use table has no accessory dwelling unit row, and in the R-R and R-1 districts section 56-40(a) and (b) each add that there shall be a maximum of one primary residence per lot. The two detached buildings the code does allow are kitchen-less by definition: accessory living quarters have no kitchen facilities and may not be rented or otherwise used as a separate residence, and a guest house has no cooking facilities and may house guests of the occupants only occasionally, with no charge. 'Casitas' is defined in section 56-31 as a small detached mother-in-law suite for guests or family members that may not be rented separately, but the word appears nowhere else in the chapter, so the definition authorizes nothing on its own. The city's own Comprehensive Plan, adopted January 2020, describes the result plainly: the R-1 district 'allows for a maximum of one primary residence per lot and does not allow accessory dwellings (such as granny flats)', and the plan's code enforcement list names 'Illegal accessory dwelling units in R-1 zones' as a live problem.

The only second-kitchen path Carlsbad offers is a multi-generational dwelling, and it is family-only and non-rentable, so it is not an ADU in the ordinary sense. Section 56-31 defines it as a building designed for residential occupancy with up to two kitchens 'for use by any number of persons related by blood, common ancestry, marriage, guardianship or adoption', and expressly excludes 'a separate structure from the principal dwelling for the purpose of renting'. Use Table 1 row 1.g lists Multiple-Generational Dwelling as 'A', meaning allowed by right subject to a zoning permit, in R-R, R-1, R-2 and C-1, and leaves the C-2, I and PUD columns blank, which section 56-41(e) says means prohibited. The two-kitchen building stays one dwelling unit rather than becoming two: an ordinary single-family dwelling is defined as having 'only one kitchen', and no use category in Chapter 56 authorizes an independent rentable unit inside or attached to a house. This is Carlsbad's implementation of the state accommodation duty in NMSA 1978 Section 3-21-1(F), and it is more generous than the statute requires, since the statute is satisfied by a conditional use permit while Carlsbad grants the use by right.

Chapter 56 controls residential bulk by lot area per dwelling unit, setbacks and height rather than by unit floor area, so there is no square-footage number to report for accessory living space. Table 6 in section 56-90 sets the minimum net lot area per dwelling unit at 10,890 sq ft in R-R with city utilities (43,560 sq ft without), 6,000 sq ft in R-1, and 2,500 sq ft in both R-2 and C-1, with maximum height 40 ft in R-R, R-1 and R-2 and 50 ft in C-1. Because a multi-generational dwelling counts as a single dwelling unit, it is bound only by those principal-building standards and adds no lot-area requirement. For detached accessory buildings, section 56-70(f)(6) caps height at 25 ft or the highest roof ridge of the principal structure, whichever is less, section 56-70(f)(1) requires at least ten feet of separation from the primary structure, and 56-70(f)(2) and (f)(3) keep accessory buildings out of the required front and side setbacks. No floor-area ratio or lot-coverage maximum appears anywhere in the chapter.

Nothing in Chapter 56 conditions a residential use on the owner living on the property. The binding restriction on the two-kitchen multi-generational dwelling is a relationship test rather than an ownership test: everyone the two kitchens serve must be 'related by blood, common ancestry, marriage, guardianship or adoption', which bites harder than a typical owner-occupancy rule but does not itself require the owner to be among them. An owner or operator residence requirement does exist in the code, but only for lodging: a bed and breakfast is defined as the subordinate use of a dwelling unit 'for which the main use is the owner's or operator's permanent residence', and the home occupation operational standards require the premises to be the primary residence of the person operating the home occupation. Since Carlsbad authorizes no accessory dwelling unit, no owner-occupancy condition attaches to one.

Section 56-100's Table 7, Parking Area Regulations for Residential Uses, lists '2 for each dwelling unit' for Single-Family Detached Dwelling (row 1.k) and the identical '2 for each dwelling unit' for Multi-Generational Dwelling (row 1.g), so adding the second kitchen adds no required space. Kitchen-less accessory buildings are not dwelling units and appear nowhere in the parking tables. If a second principal dwelling unit were ever approved on a lot it would carry its own two spaces, since the table charges per dwelling unit. Private carports, garages and off-street parking areas serving the residents and their guests are themselves listed residential accessory uses under section 56-70(d)(14), and section 56-70(d)(4) allows only one carport structure per residence.

The one path that exists is fully administrative. Because Multiple-Generational Dwelling carries an 'A' in the use table, section 56-41(b) provides that it 'is allowed by right within that zoning district' and requires only a zoning permit. Section 56-150(l)(3)(a) makes that permit ministerial: the planning director reviews the application, 'if the proposed use complies with the regulations of this code, the permit shall be granted', and 'no hearing shall be required', with a written decision inside five business days and an appeal to the Planning and Zoning Commission. A city building permit follows, because Carlsbad runs its own Building Department rather than relying on the state Construction Industries Division; the department's page lists the 2021 IRC, 2021 IBC, 2021 UPC, 2021 UMC, 2021 IECC, 2021 IFC and the 2020 NEC as the enforced codes, while section 8-28 names the city building inspector as the enforcing officer. There is no permit path at all for a detached ADU and no conditional-use route to one: the use table simply omits the category, and section 56-41(e) makes an unlisted use prohibited.

Every accessory living category in Chapter 56 is closed to renting by its own definition: accessory living quarters may not be 'rented or otherwise used as a separate residence', a casita 'shall not be intended as a residence to be rented separately from the primary residential structure on the property', a guest house may not be 'used for commercial purposes' and 'no charge is made for the use of the premises', and a multi-generational dwelling excludes 'a separate structure from the principal dwelling for the purpose of renting'. Carlsbad has no short-term rental ordinance and no residential rental licensing regime; the code's only short-stay residential use is Home Occupation, Bed and Breakfast, marked 'C' in Use Table 3 row 4.p for R-R, R-1, R-2 and C-1, with section 56-42(g) barring stays longer than two consecutive weeks, requiring that the residential character of the structure be maintained, and requiring registration with the city as a bed and breakfast. The city lodgers' tax reaches any 'hotel, motel or other premises used for lodging that is not the vendee's household or primary residence', so paid short stays are taxable whether or not zoning permits them. Living in an RV in the back yard is not a workaround either: section 56-42(s)(5)(a) allows one RV to be occupied on a residential lot for no more than 14 days in any calendar year under a temporary use permit, served only by electricity and water from the on-site dwelling, and (s)(5)(b) allows up to six months only as the owner's temporary residence at a site with an active building permit.