ADU rules in Elizabethtown

Since Ord. 17-2025 (passed 8-4-2025), 'Dwelling unit, accessory (ADU)' is a listed accessory use in every conventional residential district, R-1 through R-6, and in the C-1, C-2 and C-3 commercial districts when associated with a single-unit or duplex dwelling. A detached ADU must sit inside an accessory structure, such as a detached garage or a separate detached building, on a permanent foundation; manufactured homes, RVs, travel trailers and campers cannot be ADUs. The planned districts (PNR-1, PNR-2, PNC), C-4, C-5 downtown and the industrial districts do not list the use.

An 'integrated ADU' inside the principal building is allowed on the same by-right basis as a detached one in R-1 through R-6 (and C-1 to C-3 with a single-unit or duplex dwelling). It may be created by dividing space or adding floor area, must have its own direct outside entrance, must not make its presence obvious from the exterior, and any exterior stair to it must be on the side or rear, never the front. An addition built for it must match the principal building.

The ADU's floor area may not exceed 25 percent of the principal residential building's total square footage or 800 square feet, whichever is greater, so 800 sq ft is a floor, not a ceiling: a 4,000 sq ft house could support a 1,000 sq ft ADU. Only the ADU's own area counts, not a garage or workshop in the same accessory building. A detached ADU's building is also capped by the accessory-structure rules: all accessory structures on a residential lot together may not exceed the principal structure's square footage, and none may exceed the zone's height limit (35 ft in R-1 through R-4; up to 45 ft for some uses in R-5 and R-6).

Neither the ADU standards in § 154.076(A) nor the definition of an accessory dwelling unit in § 154.009 requires the owner to live on the property, at application or afterward. Owner occupancy matters only for short-term rental, which the code splits into owner-occupied and non-owner-occupied uses (see rental restrictions).

In the R-1 through R-6 districts one off-street parking space must be provided for the ADU on top of the two spaces per dwelling unit the district's parking table requires for the principal home. Each residential district's parking table repeats the rule ('1 additional space for an accessory dwelling unit'). The code sets no ADU-specific figure for the C-1 to C-3 districts.

The ADU is a listed accessory use, not a conditional use, so no Board of Zoning Adjustment hearing is needed; it takes the ordinary construction permit issued by the Planning and Development Department under § 154.011 and must meet the § 154.076(A) standards and the accessory-structure setbacks (no front-yard placement, at least 5 ft from side and rear lot lines and outside recorded easements).

The code's definition of a dwelling unit covers owner occupancy or rental on weekly or longer terms, and nothing in the ADU standards limits long-term renting. Stays under 30 consecutive days are short-term rentals: an owner-occupied short-term rental is an accessory use in R-1 to R-6 limited to one contract at a time, two guests per bedroom plus four, and ten rental days per calendar year, while a non-owner-occupied short-term rental is a Board of Zoning Adjustment conditional use only in R-3 to R-6 (tenure up to 30 days, liability insurance, no signs). The code does not say whether an ADU rented nightly while the owner lives in the main house counts as owner occupied. There is no separate short-term rental license in the business regulations (Title XI).