ADU rules in Lockhart

Lockhart has two ADU classes, and both may be built in a permanent detached accessory structure on the same lot as a single-family home (Sec. 64-2). ADU Limited (owner-occupied, up to 600 sq ft) is allowed by right in the RMD and RHD districts but needs a specific use permit from the Planning and Zoning Commission in RLD, the city's main single-family district. ADU General (up to 1,000 sq ft, no owner-occupancy rule) is allowed by right only in RHD, needs a specific use permit in RMD, and is not listed at all in RLD; it is also limited to lots big enough for a by-right duplex, which in RMD means the DF-1 standard of 8,500 sq ft and 65 by 120 ft. Neither class is listed in the agricultural, commercial, industrial, manufactured home or planned development districts, and in the flood hazard district either class needs a specific use permit.

The same district split applies to an ADU inside or attached to the house, because both classes are defined as a secondary unit 'within or attached to a single-family dwelling' or in a detached accessory structure (Sec. 64-2). ADU Limited is by right in RMD and RHD and by specific use permit in RLD; ADU General is by right in RHD, by specific use permit in RMD (on a lot meeting the 8,500 sq ft, 65 by 120 ft DF-1 duplex standard) and unavailable in RLD. Only one ADU of either class is allowed per lot.

Both caps use 'whichever is greater', so a large house raises the limit: behind a 2,400 sq ft house either class could reach 1,200 sq ft. ADU General is also confined to a lot of the size and dimensions where a duplex is allowed by right (DF-1: 8,500 sq ft, 65 by 120 ft, in RMD and RHD; DF-2: 6,000 sq ft, 50 by 105 ft, by right only in RHD). The code sets no separate ADU height, footprint or setback rule: a detached unit follows the district development-type standards in Appendix I (for SF-1 lots, 2.5 stories, 30 percent lot coverage, 25 ft street, 7.5 ft side and 10 ft rear setbacks) and Sec. 64-197(b), which bars any building in a required yard.

It depends on the class. ADU Limited exists only 'where the owner of the property resides in either the primary dwelling unit or the accessory dwelling unit', an ongoing condition with no time limit, and the unit must also share the main house's electric meter. ADU General has no owner-occupancy clause, which is the trade-off for its stricter district, lot-size and parking rules. Texas has no state ADU law, so nothing preempts either rule.

Both requirements come on top of the primary home's own minimum, which Appendix I sets at 2 spaces plus 1 for each bedroom over 3 (garages excluded). Driveways may count as off-street parking in residential districts, and in RLD and RMD the parking must be on the same tract (Sec. 64-197(g)(2)b and c). A specific use permit can add parking or access conditions (Sec. 64-127(c)(6)b).

Where an ADU is allowed by right (ADU Limited in RMD and RHD, ADU General in RHD), the route is an ordinary building permit under Sec. 64-126. Elsewhere it needs a specific use permit: ADU Limited in RLD, ADU General in RMD, and either class in the flood hazard district. The Planning and Zoning Commission decides those after a public hearing with mailed notice to owners within 200 feet. It may attach conditions, and it may deny if the use creates greater impacts than a by-right use or if owners of 30 percent of the land within 200 feet protest in writing. Anyone aggrieved may appeal to the city council within ten days. The SUP fee is $250 plus $150 per acre (maximum $2,500).

ADU Limited may be 'occupied by no more than two people who are family members, guests, or caretakers or other domestic employees' of the owner-occupant, which rules out an ordinary tenant. ADU General carries no occupancy or owner clause, so a long-term lease is not restricted by Chapter 64. Any rental under 30 days in a residential district must be registered with the Finance Department ($50, one-year term), which brings a cap of two adults per bedroom and ten people in total, one off-street space per bedroom, smoke and CO alarms and an extinguisher, and a no-party notice in every listing. The 7 percent city hotel occupancy tax applies to those stays (Sec. 54-117). Ord. 2026-14 (passed 4-7-2026, not yet codified) adds short-term rentals to the tax's hotel definition and requires listing platforms to collect it. The code does not say whether a paying nightly 'guest' fits the ADU Limited occupancy clause, so short-term rental of a Limited unit is uncertain.