ADU rules in Lexington

Lexington's zoning ordinance has no accessory dwelling unit use. In the R-1, R-2, R-3 and R-4 residential districts a lot may hold only one principal building (§4.06.01), R-1 permits 'One single-family dwelling per zone lot' (§5.07.02), and the only lodging allowed in a detached outbuilding is 'accessory living quarters' for temporary guests with no kitchen that may not be rented or used as a separate dwelling unit, which is not an ADU. The one route to a second detached home is in the A-1 Agricultural and A-2 Transitional Agriculture districts, where 'One additional single-family dwelling for the purpose of housing relatives or agricultural workers' is a conditional use (§5.05.03(12), §5.06.03(8)) approved by the City Council after Planning Commission and Council hearings. Those districts require 10-acre residential lots and lie mostly in the two-mile extraterritorial ring, so on an ordinary city lot a backyard cottage is not possible.

There is no attached, basement or internal ADU use either. The only lawful way to put a second unit inside or onto a house is a two-family dwelling (duplex), defined as a building 'designed or used exclusively for the occupancy of two families living independently of each other and having separate kitchen and toilet facilities for each family' (§2.02). Two-family dwellings are permitted by right in R-2 (§5.08.02(3)) and R-3 (§5.09.02(6)), but not in R-1 Single-Family Residential, R-4 or the agricultural districts. The lot must meet the duplex standard: 10,890 sq ft and 75 ft of width in R-2, or 7,260 sq ft and 75 ft in R-3, against 7,000 sq ft (R-2) for a single-family home.

Because the code has no ADU use, it sets no ADU size limit. The A-1/A-2 additional dwelling is a 'single-family dwelling', which by definition must have at least 900 sq ft of above-grade floor area for single-story construction and an 18 ft minimum width, and it falls under the district's 35 ft height and 20 percent lot coverage limits; the Council may add conditions in the conditional use agreement. A duplex in R-2 is bounded by the district's 10,890 sq ft lot, 75 ft width, 50 percent coverage and 35 ft height; in R-3 the lot minimum is 7,260 sq ft. Accessory buildings in residential districts must stay subordinate to the house in size and footprint, with sidewalls no taller than 15 ft (§§4.13.02, 4.13.08), and in R-2 no accessory building may exceed the ground-floor coverage of the house (§5.08.04(1)).

No section of the zoning ordinance requires the owner to live on the property for either route. The A-1/A-2 additional dwelling is restricted by occupant instead: it may be used only 'for the purpose of housing relatives or agricultural workers'. A duplex in R-2 or R-3 carries no residency requirement. The only owner-residence rule in the residential chapters applies to a bed and breakfast, whose 'owner and/or host shall reside on the premises' (§2.02).

Every dwelling unit needs two off-street spaces: §7.01.01(1) requires 'Dwellings - Two (2) spaces for each dwelling unit.' The §7.02 schedule repeats this as 'Two spaces per dwelling unit' for a duplex and 'Two spaces per dwelling unit with one required to be enclosed' for single-family homes, so an A-1/A-2 additional dwelling adds two spaces (one in a garage) and a duplex needs four in total. The Building Official may allow required spaces on other off-street property within 400 ft (§7.01.02).

The route depends on the form. The A-1/A-2 additional single-family dwelling is a conditional use: under §§6.01 to 6.05 the Planning Commission holds a public hearing and recommends, the City Council holds its own hearing and grants or denies by majority vote, and an approval takes the form of a signed conditional use agreement that lapses if the use does not start within 12 months. A duplex in R-2 or R-3 is a permitted use that needs only a building permit and certificate of occupancy (§4.13.03 bars using any accessory building as a dwelling without a certificate of occupancy).

The agricultural-district additional dwelling may house only relatives or agricultural workers, so it cannot be let to the general public, and 'accessory living quarters' in an outbuilding must not be 'rented or otherwise used as a separate dwelling unit' (§2.02). Duplex units in R-2 and R-3 may be rented long term with no city rental license or inspection program; quoted searches of the Municode City Code for 'short-term', 'short term', 'rental housing' and 'lodging' returned no sections. A bed and breakfast (owner or host on site, up to five guest rooms) is a conditional use in every residential and agricultural district, but its lodging rooms must be in the principal building, 'not within an accessory building' (§7.19.01(2)).